三角函数数值表
sin tan cos三角函数表高中
sin tan cos三角函数表高中
下面列出了高中数学中常用的sin、cos和tan三角函数表格，方便同学们快速查阅。
角度（度）角度（弧
度）
正弦
（sin）
余弦
（cos）
正切
（tan）
00010
30π/61/2√3/2√3/3
45π/4√2/2√2/21
60π/3√3/21/2√3
90π/210无穷大
利用这个三角函数表格，我们可以获得不同角度下的正弦、余弦和正切值，进而解决各种三角函数相关的问题。
在求解三角函数问题时，可以利用这个表格帮助我们快速定位角度与对应函数值，提高解题效率。
除了以上列出的几个常用角度外，我们还可以通过特殊角
的关系，根据基本角（0°、30°、45°、60°、90°）的正弦、余弦和正切值，推导出其他角度的三角函数值。
通过不断练习和熟练掌握三角函数的数值，可以为高中数学学习打下坚实的基础。
希望这份三角函数表格能够帮助同学们更好地理解和运用
三角函数知识，解决数学学习中遇到的问题。
愿大家在数学学习的道路上取得更多的成就！。
(完整版)三角函数特殊角值表
角度 函数 0 30 45 60 90 120 135 150 180 270 360 角a 的弧度0 π/6 π/4 π/3 π/2 2π/3 3π/4 5π/6 π 3π/2 2π sin 0 1/2 √2/2 √3/2 1 √3/2 √2/2 1/2 0 -1 0 cos 1 √3/2 √2/2 1/2 0 -1/2 -√2/2 -√3/2 -1 0 1 tan√3/31√3-√3-1-√3/31、图示法：借助于下面三个图形来记忆，即使有所遗忘也可根据图形重新推出： sin30°=cos60°=21，sin45°=cos45°=22， tan30°=cot60°=33， tan 45°=cot45°=1正弦函数 sinθ=y/r 余弦函数 cosθ=x/r 正切函数 tanθ=y/x 余切函数 cotθ=x/y 正割函数 secθ=r/x 余割函数 cscθ=r/y2、列表法：说明：正弦值随角度变化，即0˚ 30˚ 45˚ 60˚ 90˚变化；值从02122 23 1变化，其余类似记忆．3、规律记忆法：观察表中的数值特征，可总结为下列记忆规律：① 有界性：（锐角三角函数值都是正值）即当0°＜α＜90°时，则0＜sin α＜1； 0＜cos α＜1 ； tan α＞0 ； cot α＞0。
②增减性：（锐角的正弦、正切值随角度的增大而增大；余弦、余切值随角度的增大而减小），即当0＜A ＜B ＜90°时，则sin A ＜sin B ；tan A ＜tan B ； cos A ＞cos B ；cot A ＞cot B ；特别地：若0°＜α＜45°，则sin A ＜cos A ；tan A ＜cot A 若45°＜A ＜90°，则sin A ＞cos A ；tan A ＞cot A ． 4、口决记忆法：观察表中的数值特征 正弦、余弦值可表示为2m 形式，正切、余切值可表示为3m 形式，有关m 的值可归纳成顺口溜：一、二、三；三、二、一；三九二十七．30˚ 123145˚ 1212 60˚ 3函数名正弦余弦正切余切正割余割符号sin cos tan cot sec csc正弦函数sin（A）=a/c余弦函数cos（A）=b/c正切函数tan（A）=a/b余切函数cot（A）=b/a其中a为对边，b为邻边，c为斜边三角函数对照表三角函数SIN COS TAN 三角函数SIN COS TAN 0°0 1 0 90° 1 0 无1°0.0174 0.9998 0.0174 89°0.9998 0.0174 57.2899 2°0.0348 0.9993 0.0349 88°0.9993 0.0348 28.6362 3°0.0523 0.9986 0.0524 87°0.9986 0.0523 19.0811 4°0.0697 0.9975 0.0699 86°0.9975 0.0697 14.3006 5°0.0871 0.9961 0.0874 85°0.9961 0.0871 11.4300 6°0.1045 0.9945 0.1051 84°0.9945 0.1045 9.5143 7°0.1218 0.9925 0.1227 83°0.9925 0.1218 8.1443 8°0.1391 0.9902 0.1405 82°0.9902 0.1391 7.1153 9°0.1564 0.9876 0.1583 81°0.9876 0.1564 6.3137 10°0.1736 0.9848 0.1763 80°0.9848 0.1736 5.6712 11°0.1908 0.9816 0.1943 79°0.9816 0.1908 5.1445 12°0.2079 0.9781 0.2125 78°0.9781 0.2079 4.7046 13°0.2249 0.9743 0.2308 77°0.9743 0.2249 4.3314 14°0.2419 0.9702 0.2493 76°0.9702 0.2419 4.0107 15°0.2588 0.9659 0.2679 75°0.9659 0.2588 3.7320二倍角的正弦、余弦和正切公式三倍角的正弦、余弦和正切公式sin 22sin cos cos 2cos 2sin 22cos 2112sin 2αααααααα==-=-=-2tan tan 21tan 2ααα=--sin 33sin 4sin 3cos34cos33cos .3tan tan 3tan 313tan 2αααααααααα=-=--=--三角函数的和差化积公式 三角函数的积化和差公式sin sin 2sincos 22sin sin 2cos sin22cos cos 2cos cos22cos cos 2sin sin22αβαβαβαβαβαβαβαβαβαβαβαβ+-+=⋅+--=⋅+-+=⋅+--=-⋅[][][][]1sin cos sin()sin()21cos sin sin()sin()21cos cos cos()cos()21sin sin cos()cos()2αβαβαβαβαβαβαβαβαβαβαβαβ⋅=++-⋅=+--⋅=++-⋅=-+--化asinα ±bcosα为一个角的一个三角函数的形式（辅助角的三角函数的公式）22sin cos sin()a x b x a b x φ±=+±其中φ角所在的象限由a 、b 的符号确定，φ角的值由tan ba φ=确定六边形记忆法：图形结构“上弦中切下割，左正右余中间1”；记忆方法“对角线上两个函数的积为1；阴影三角形上两顶点的三角函数值的平方和等于下顶点的三角函数值的平方；任意一顶点的三角函数值等于相邻两个顶点的三角函数值的乘积。
三角函数特殊角值表
三角函数特殊角函数值
只想上传这一个表 下面的都是无用的话 不用看了。
1、图示法：借助于下面三个图形来记忆，即使有所遗忘也可根据图形重新推出： sin30°=cos60°=
2
1
sin45°=cos45°=22
tan30°=cot60°=3
3
tan 45°=cot45°=1
2、列表法：
说明：正弦值随角度变化，即0? 30? 45? 60? 90?变化；值从0
30? 1
2
3 1
45? 1
2 1
2 60? 3
变化，其余类似记忆．
3、规律记忆法：观察表中的数值特征，可总结为下列记忆规律：
①有界性：（锐角三角函数值都是正值）即当0°＜α＜90°时，
则0＜sinα＜1； 0＜cosα＜1 ； tanα＞0 ； cotα＞0。
②增减性：（锐角的正弦、正切值随角度的增大而增大；余弦、余切值随角度的增大而减小），即当0＜A＜B＜90°时，则sin A＜sin B；tan A＜tan B； cos A＞cos B；cot A＞cot B；特别地：若0°＜α＜45°，则sin A＜cos A；tan A＜cot A
若45°＜A＜90°，则sin A＞cos A；tan A＞cot A．
4、口决记忆法：观察表中的数值特征
正弦、余弦值可表示为
2
m形式，正切、余切值可表示为
3
m形式，有关m的值可归纳成顺口溜：一、二、三；三、二、一；三九二十七．。
cos函数度数表
三角函数0~360°度数表sin(0°)=0.000000,cos(0°)=1.000000,tan(0°)=0.000000 sin(1°)=0.017452,cos(1°)=0.999848,tan(1°)=0.017455 sin(2°)=0.034899,cos(2°)=0.999391,tan(2°)=0.034921 sin(3°)=0.052336,cos(3°)=0.998630,tan(3°)=0.052408 sin(4°)=0.069756,cos(4°)=0.997564,tan(4°)=0.069927 sin(5°)=0.087156,cos(5°)=0.996195,tan(5°)=0.087489 sin(6°)=0.104528,cos(6°)=0.994522,tan(6°)=0.105104 sin(7°)=0.121869,cos(7°)=0.992546,tan(7°)=0.122785 sin(8°)=0.139173,cos(8°)=0.990268,tan(8°)=0.140541 sin(9°)=0.156434,cos(9°)=0.987688,tan(9°)=0.158384 sin(10°)=0.173648,cos(10°)=0.984808,tan(10°)=0.176327 sin(11°)=0.190809,cos(11°)=0.981627,tan(11°)=0.194380sin(12°)=0.207912,cos(12°)=0.978148,tan(12°)=0.212557 sin(13°)=0.224951,cos(13°)=0.974370,tan(13°)=0.230868 sin(14°)=0.241922,cos(14°)=0.970296,tan(14°)=0.249328 sin(15°)=0.258819,cos(15°)=0.965926,tan(15°)=0.267949 sin(16°)=0.275637,cos(16°)=0.961262,tan(16°)=0.286745 sin(17°)=0.292372,cos(17°)=0.956305,tan(17°)=0.305731 sin(18°)=0.309017,cos(18°)=0.951057,tan(18°)=0.324920 sin(19°)=0.325568,cos(19°)=0.945519,tan(19°)=0.344328 sin(20°)=0.342020,cos(20°)=0.939693,tan(20°)=0.363970 sin(21°)=0.358368,cos(21°)=0.933580,tan(21°)=0.383864 sin(22°)=0.374607,cos(22°)=0.927184,tan(22°)=0.404026 sin(23°)=0.390731,cos(23°)=0.920505,tan(23°)=0.424475 sin(24°)=0.406737,cos(24°)=0.913545,tan(24°)=0.445229sin(25°)=0.422618,cos(25°)=0.906308,tan(25°)=0.466308 sin(26°)=0.438371,cos(26°)=0.898794,tan(26°)=0.487733 sin(27°)=0.453990,cos(27°)=0.891007,tan(27°)=0.509525 sin(28°)=0.469472,cos(28°)=0.882948,tan(28°)=0.531709 sin(29°)=0.484810,cos(29°)=0.874620,tan(29°)=0.554309 sin(30°)=0.500000,cos(30°)=0.866025,tan(30°)=0.577350 sin(31°)=0.515038,cos(31°)=0.857167,tan(31°)=0.600861 sin(32°)=0.529919,cos(32°)=0.848048,tan(32°)=0.624869 sin(33°)=0.544639,cos(33°)=0.838671,tan(33°)=0.649408 sin(34°)=0.559193,cos(34°)=0.829038,tan(34°)=0.674509 sin(35°)=0.573576,cos(35°)=0.819152,tan(35°)=0.700208 sin(36°)=0.587785,cos(36°)=0.809017,tan(36°)=0.726543 sin(37°)=0.601815,cos(37°)=0.798636,tan(37°)=0.753554sin(38°)=0.615661,cos(38°)=0.788011,tan(38°)=0.781286 sin(39°)=0.629320,cos(39°)=0.777146,tan(39°)=0.809784 sin(40°)=0.642788,cos(40°)=0.766044,tan(40°)=0.839100 sin(41°)=0.656059,cos(41°)=0.754710,tan(41°)=0.869287 sin(42°)=0.669131,cos(42°)=0.743145,tan(42°)=0.900404 sin(43°)=0.681998,cos(43°)=0.731354,tan(43°)=0.932515 sin(44°)=0.694658,cos(44°)=0.719340,tan(44°)=0.965689 sin(45°)=0.707107,cos(45°)=0.707107,tan(45°)=1.000000 sin(46°)=0.719340,cos(46°)=0.694658,tan(46°)=1.035530 sin(47°)=0.731354,cos(47°)=0.681998,tan(47°)=1.072369 sin(48°)=0.743145,cos(48°)=0.669131,tan(48°)=1.110613 sin(49°)=0.754710,cos(49°)=0.656059,tan(49°)=1.150368 sin(50°)=0.766044,cos(50°)=0.642788,tan(50°)=1.191754sin(51°)=0.777146,cos(51°)=0.629320,tan(51°)=1.234897 sin(52°)=0.788011,cos(52°)=0.615661,tan(52°)=1.279942 sin(53°)=0.798636,cos(53°)=0.601815,tan(53°)=1.327045 sin(54°)=0.809017,cos(54°)=0.587785,tan(54°)=1.376382 sin(55°)=0.819152,cos(55°)=0.573576,tan(55°)=1.428148 sin(56°)=0.829038,cos(56°)=0.559193,tan(56°)=1.482561 sin(57°)=0.838671,cos(57°)=0.544639,tan(57°)=1.539865 sin(58°)=0.848048,cos(58°)=0.529919,tan(58°)=1.600335 sin(59°)=0.857167,cos(59°)=0.515038,tan(59°)=1.664279 sin(60°)=0.866025,cos(60°)=0.500000,tan(60°)=1.732051 sin(61°)=0.874620,cos(61°)=0.484810,tan(61°)=1.804048 sin(62°)=0.882948,cos(62°)=0.469472,tan(62°)=1.880726 sin(63°)=0.891007,cos(63°)=0.453990,tan(63°)=1.962611sin(64°)=0.898794,cos(64°)=0.438371,tan(64°)=2.050304 sin(65°)=0.906308,cos(65°)=0.422618,tan(65°)=2.144507 sin(66°)=0.913545,cos(66°)=0.406737,tan(66°)=2.246037 sin(67°)=0.920505,cos(67°)=0.390731,tan(67°)=2.355852 sin(68°)=0.927184,cos(68°)=0.374607,tan(68°)=2.475087 sin(69°)=0.933580,cos(69°)=0.358368,tan(69°)=2.605089 sin(70°)=0.939693,cos(70°)=0.342020,tan(70°)=2.747477 sin(71°)=0.945519,cos(71°)=0.325568,tan(71°)=2.904211 sin(72°)=0.951057,cos(72°)=0.309017,tan(72°)=3.077684 sin(73°)=0.956305,cos(73°)=0.292372,tan(73°)=3.270853 sin(74°)=0.961262,cos(74°)=0.275637,tan(74°)=3.487414 sin(75°)=0.965926,cos(75°)=0.258819,tan(75°)=3.732051 sin(76°)=0.970296,cos(76°)=0.241922,tan(76°)=4.010781sin(77°)=0.974370,cos(77°)=0.224951,tan(77°)=4.331476 sin(78°)=0.978148,cos(78°)=0.207912,tan(78°)=4.704630 sin(79°)=0.981627,cos(79°)=0.190809,tan(79°)=5.144554 sin(80°)=0.984808,cos(80°)=0.173648,tan(80°)=5.671282 sin(81°)=0.987688,cos(81°)=0.156434,tan(81°)=6.313752 sin(82°)=0.990268,cos(82°)=0.139173,tan(82°)=7.115370 sin(83°)=0.992546,cos(83°)=0.121869,tan(83°)=8.144346 sin(84°)=0.994522,cos(84°)=0.104528,tan(84°)=9.514364 sin(85°)=0.996195,cos(85°)=0.087156,tan(85°)=11.430052 sin(86°)=0.997564,cos(86°)=0.069756,tan(86°)=14.300666 sin(87°)=0.998630,cos(87°)=0.052336,tan(87°)=19.081137 sin(88°)=0.999391,cos(88°)=0.034899,tan(88°)=28.636253 sin(89°)=0.999848,cos(89°)=0.017452,tan(89°)=57.289962sin(90°)=1.000000,cos(90°)=0.000000,tan(90°)=无意义sin(91°)=0.999848,cos(91°)=-0.017452,tan(91°)=-57.289962 sin(92°)=0.999391,cos(92°)=-0.034899,tan(92°)=-28.636253 sin(93°)=0.998630,cos(93°)=-0.052336,tan(93°)=-19.081137 sin(94°)=0.997564,cos(94°)=-0.069756,tan(94°)=-14.300666 sin(95°)=0.996195,cos(95°)=-0.087156,tan(95°)=-11.430052 sin(96°)=0.994522,cos(96°)=-0.104528,tan(96°)=-9.514364 sin(97°)=0.992546,cos(97°)=-0.121869,tan(97°)=-8.144346 sin(98°)=0.990268,cos(98°)=-0.139173,tan(98°)=-7.115370 sin(99°)=0.987688,cos(99°)=-0.156434,tan(99°)=-6.313752 sin(100°)=0.984808,cos(100°)=-0.173648,tan(100°)=-5.671282 sin(101°)=0.981627,cos(101°)=-0.190809,tan(101°)=-5.144554 sin(102°)=0.978148,cos(102°)=-0.207912,tan(102°)=-4.704630sin(103°)=0.974370,cos(103°)=-0.224951,tan(103°)=-4.331476 sin(104°)=0.970296,cos(104°)=-0.241922,tan(104°)=-4.010781 sin(105°)=0.965926,cos(105°)=-0.258819,tan(105°)=-3.732051 sin(106°)=0.961262,cos(106°)=-0.275637,tan(106°)=-3.487414 sin(107°)=0.956305,cos(107°)=-0.292372,tan(107°)=-3.270853 sin(108°)=0.951057,cos(108°)=-0.309017,tan(108°)=-3.077684 sin(109°)=0.945519,cos(109°)=-0.325568,tan(109°)=-2.904211 sin(110°)=0.939693,cos(110°)=-0.342020,tan(110°)=-2.747477 sin(111°)=0.933580,cos(111°)=-0.358368,tan(111°)=-2.605089 sin(112°)=0.927184,cos(112°)=-0.374607,tan(112°)=-2.475087 sin(113°)=0.920505,cos(113°)=-0.390731,tan(113°)=-2.355852 sin(114°)=0.913545,cos(114°)=-0.406737,tan(114°)=-2.246037 sin(115°)=0.906308,cos(115°)=-0.422618,tan(115°)=-2.144507sin(116°)=0.898794,cos(116°)=-0.438371,tan(116°)=-2.050304 sin(117°)=0.891007,cos(117°)=-0.453990,tan(117°)=-1.962611 sin(118°)=0.882948,cos(118°)=-0.469472,tan(118°)=-1.880726 sin(119°)=0.874620,cos(119°)=-0.484810,tan(119°)=-1.804048 sin(120°)=0.866025,cos(120°)=-0.500000,tan(120°)=-1.732051 sin(121°)=0.857167,cos(121°)=-0.515038,tan(121°)=-1.664279 sin(122°)=0.848048,cos(122°)=-0.529919,tan(122°)=-1.600335 sin(123°)=0.838671,cos(123°)=-0.544639,tan(123°)=-1.539865 sin(124°)=0.829038,cos(124°)=-0.559193,tan(124°)=-1.482561 sin(125°)=0.819152,cos(125°)=-0.573576,tan(125°)=-1.428148 sin(126°)=0.809017,cos(126°)=-0.587785,tan(126°)=-1.376382 sin(127°)=0.798636,cos(127°)=-0.601815,tan(127°)=-1.327045 sin(128°)=0.788011,cos(128°)=-0.615661,tan(128°)=-1.279942sin(129°)=0.777146,cos(129°)=-0.629320,tan(129°)=-1.234897 sin(130°)=0.766044,cos(130°)=-0.642788,tan(130°)=-1.191754 sin(131°)=0.754710,cos(131°)=-0.656059,tan(131°)=-1.150368 sin(132°)=0.743145,cos(132°)=-0.669131,tan(132°)=-1.110613 sin(133°)=0.731354,cos(133°)=-0.681998,tan(133°)=-1.072369 sin(134°)=0.719340,cos(134°)=-0.694658,tan(134°)=-1.035530 sin(135°)=0.707107,cos(135°)=-0.707107,tan(135°)=-1.000000 sin(136°)=0.694658,cos(136°)=-0.719340,tan(136°)=-0.965689 sin(137°)=0.681998,cos(137°)=-0.731354,tan(137°)=-0.932515 sin(138°)=0.669131,cos(138°)=-0.743145,tan(138°)=-0.900404 sin(139°)=0.656059,cos(139°)=-0.754710,tan(139°)=-0.869287 sin(140°)=0.642788,cos(140°)=-0.766044,tan(140°)=-0.839100 sin(141°)=0.629320,cos(141°)=-0.777146,tan(141°)=-0.809784sin(142°)=0.615661,cos(142°)=-0.788011,tan(142°)=-0.781286 sin(143°)=0.601815,cos(143°)=-0.798636,tan(143°)=-0.753554 sin(144°)=0.587785,cos(144°)=-0.809017,tan(144°)=-0.726543 sin(145°)=0.573576,cos(145°)=-0.819152,tan(145°)=-0.700208 sin(146°)=0.559193,cos(146°)=-0.829038,tan(146°)=-0.674509 sin(147°)=0.544639,cos(147°)=-0.838671,tan(147°)=-0.649408 sin(148°)=0.529919,cos(148°)=-0.848048,tan(148°)=-0.624869 sin(149°)=0.515038,cos(149°)=-0.857167,tan(149°)=-0.600861 sin(150°)=0.500000,cos(150°)=-0.866025,tan(150°)=-0.577350 sin(151°)=0.484810,cos(151°)=-0.874620,tan(151°)=-0.554309 sin(152°)=0.469472,cos(152°)=-0.882948,tan(152°)=-0.531709 sin(153°)=0.453990,cos(153°)=-0.891007,tan(153°)=-0.509525 sin(154°)=0.438371,cos(154°)=-0.898794,tan(154°)=-0.487733sin(155°)=0.422618,cos(155°)=-0.906308,tan(155°)=-0.466308 sin(156°)=0.406737,cos(156°)=-0.913545,tan(156°)=-0.445229 sin(157°)=0.390731,cos(157°)=-0.920505,tan(157°)=-0.424475 sin(158°)=0.374607,cos(158°)=-0.927184,tan(158°)=-0.404026 sin(159°)=0.358368,cos(159°)=-0.933580,tan(159°)=-0.383864 sin(160°)=0.342020,cos(160°)=-0.939693,tan(160°)=-0.363970 sin(161°)=0.325568,cos(161°)=-0.945519,tan(161°)=-0.344328 sin(162°)=0.309017,cos(162°)=-0.951057,tan(162°)=-0.324920 sin(163°)=0.292372,cos(163°)=-0.956305,tan(163°)=-0.305731 sin(164°)=0.275637,cos(164°)=-0.961262,tan(164°)=-0.286745 sin(165°)=0.258819,cos(165°)=-0.965926,tan(165°)=-0.267949 sin(166°)=0.241922,cos(166°)=-0.970296,tan(166°)=-0.249328 sin(167°)=0.224951,cos(167°)=-0.974370,tan(167°)=-0.230868sin(169°)=0.190809,cos(169°)=-0.981627,tan(169°)=-0.194380 sin(170°)=0.173648,cos(170°)=-0.984808,tan(170°)=-0.176327 sin(171°)=0.156434,cos(171°)=-0.987688,tan(171°)=-0.158384 sin(172°)=0.139173,cos(172°)=-0.990268,tan(172°)=-0.140541 sin(173°)=0.121869,cos(173°)=-0.992546,tan(173°)=-0.122785 sin(174°)=0.104528,cos(174°)=-0.994522,tan(174°)=-0.105104 sin(175°)=0.087156,cos(175°)=-0.996195,tan(175°)=-0.087489 sin(176°)=0.069756,cos(176°)=-0.997564,tan(176°)=-0.069927 sin(177°)=0.052336,cos(177°)=-0.998630,tan(177°)=-0.052408 sin(178°)=0.034899,cos(178°)=-0.999391,tan(178°)=-0.034921 sin(179°)=0.017452,cos(179°)=-0.999848,tan(179°)=-0.017455 sin(180°)=0.000000,cos(180°)=-1.000000,tan(180°)=-0.000000sin(182°)=-0.034899,cos(182°)=-0.999391,tan(182°)=0.034921 sin(183°)=-0.052336,cos(183°)=-0.998630,tan(183°)=0.052408 sin(184°)=-0.069756,cos(184°)=-0.997564,tan(184°)=0.069927 sin(185°)=-0.087156,cos(185°)=-0.996195,tan(185°)=0.087489 sin(186°)=-0.104528,cos(186°)=-0.994522,tan(186°)=0.105104 sin(187°)=-0.121869,cos(187°)=-0.992546,tan(187°)=0.122785 sin(188°)=-0.139173,cos(188°)=-0.990268,tan(188°)=0.140541 sin(189°)=-0.156434,cos(189°)=-0.987688,tan(189°)=0.158384 sin(190°)=-0.173648,cos(190°)=-0.984808,tan(190°)=0.176327 sin(191°)=-0.190809,cos(191°)=-0.981627,tan(191°)=0.194380 sin(192°)=-0.207912,cos(192°)=-0.978148,tan(192°)=0.212557 sin(193°)=-0.224951,cos(193°)=-0.974370,tan(193°)=0.230868sin(194°)=-0.241922,cos(194°)=-0.970296,tan(194°)=0.249328 sin(195°)=-0.258819,cos(195°)=-0.965926,tan(195°)=0.267949 sin(196°)=-0.275637,cos(196°)=-0.961262,tan(196°)=0.286745 sin(197°)=-0.292372,cos(197°)=-0.956305,tan(197°)=0.305731 sin(198°)=-0.309017,cos(198°)=-0.951057,tan(198°)=0.324920 sin(199°)=-0.325568,cos(199°)=-0.945519,tan(199°)=0.344328 sin(200°)=-0.342020,cos(200°)=-0.939693,tan(200°)=0.363970 sin(201°)=-0.358368,cos(201°)=-0.933580,tan(201°)=0.383864 sin(202°)=-0.374607,cos(202°)=-0.927184,tan(202°)=0.404026 sin(203°)=-0.390731,cos(203°)=-0.920505,tan(203°)=0.424475 sin(204°)=-0.406737,cos(204°)=-0.913545,tan(204°)=0.445229 sin(205°)=-0.422618,cos(205°)=-0.906308,tan(205°)=0.466308 sin(206°)=-0.438371,cos(206°)=-0.898794,tan(206°)=0.487733sin(207°)=-0.453990,cos(207°)=-0.891007,tan(207°)=0.509525 sin(208°)=-0.469472,cos(208°)=-0.882948,tan(208°)=0.531709 sin(209°)=-0.484810,cos(209°)=-0.874620,tan(209°)=0.554309 sin(210°)=-0.500000,cos(210°)=-0.866025,tan(210°)=0.577350 sin(211°)=-0.515038,cos(211°)=-0.857167,tan(211°)=0.600861 sin(212°)=-0.529919,cos(212°)=-0.848048,tan(212°)=0.624869 sin(213°)=-0.544639,cos(213°)=-0.838671,tan(213°)=0.649408 sin(214°)=-0.559193,cos(214°)=-0.829038,tan(214°)=0.674509 sin(215°)=-0.573576,cos(215°)=-0.819152,tan(215°)=0.700208 sin(216°)=-0.587785,cos(216°)=-0.809017,tan(216°)=0.726543 sin(217°)=-0.601815,cos(217°)=-0.798636,tan(217°)=0.753554 sin(218°)=-0.615661,cos(218°)=-0.788011,tan(218°)=0.781286 sin(219°)=-0.629320,cos(219°)=-0.777146,tan(219°)=0.809784sin(220°)=-0.642788,cos(220°)=-0.766044,tan(220°)=0.839100 sin(221°)=-0.656059,cos(221°)=-0.754710,tan(221°)=0.869287 sin(222°)=-0.669131,cos(222°)=-0.743145,tan(222°)=0.900404 sin(223°)=-0.681998,cos(223°)=-0.731354,tan(223°)=0.932515 sin(224°)=-0.694658,cos(224°)=-0.719340,tan(224°)=0.965689 sin(225°)=-0.707107,cos(225°)=-0.707107,tan(225°)=1.000000 sin(226°)=-0.719340,cos(226°)=-0.694658,tan(226°)=1.035530 sin(227°)=-0.731354,cos(227°)=-0.681998,tan(227°)=1.072369 sin(228°)=-0.743145,cos(228°)=-0.669131,tan(228°)=1.110613 sin(229°)=-0.754710,cos(229°)=-0.656059,tan(229°)=1.150368 sin(230°)=-0.766044,cos(230°)=-0.642788,tan(230°)=1.191754 sin(231°)=-0.777146,cos(231°)=-0.629320,tan(231°)=1.234897 sin(232°)=-0.788011,cos(232°)=-0.615661,tan(232°)=1.279942sin(233°)=-0.798636,cos(233°)=-0.601815,tan(233°)=1.327045 sin(234°)=-0.809017,cos(234°)=-0.587785,tan(234°)=1.376382 sin(235°)=-0.819152,cos(235°)=-0.573576,tan(235°)=1.428148 sin(236°)=-0.829038,cos(236°)=-0.559193,tan(236°)=1.482561 sin(237°)=-0.838671,cos(237°)=-0.544639,tan(237°)=1.539865 sin(238°)=-0.848048,cos(238°)=-0.529919,tan(238°)=1.600335 sin(239°)=-0.857167,cos(239°)=-0.515038,tan(239°)=1.664279 sin(240°)=-0.866025,cos(240°)=-0.500000,tan(240°)=1.732051 sin(241°)=-0.874620,cos(241°)=-0.484810,tan(241°)=1.804048 sin(242°)=-0.882948,cos(242°)=-0.469472,tan(242°)=1.880726 sin(243°)=-0.891007,cos(243°)=-0.453990,tan(243°)=1.962611 sin(244°)=-0.898794,cos(244°)=-0.438371,tan(244°)=2.050304 sin(245°)=-0.906308,cos(245°)=-0.422618,tan(245°)=2.144507sin(246°)=-0.913545,cos(246°)=-0.406737,tan(246°)=2.246037 sin(247°)=-0.920505,cos(247°)=-0.390731,tan(247°)=2.355852 sin(248°)=-0.927184,cos(248°)=-0.374607,tan(248°)=2.475087 sin(249°)=-0.933580,cos(249°)=-0.358368,tan(249°)=2.605089 sin(250°)=-0.939693,cos(250°)=-0.342020,tan(250°)=2.747477 sin(251°)=-0.945519,cos(251°)=-0.325568,tan(251°)=2.904211 sin(252°)=-0.951057,cos(252°)=-0.309017,tan(252°)=3.077684 sin(253°)=-0.956305,cos(253°)=-0.292372,tan(253°)=3.270853 sin(254°)=-0.961262,cos(254°)=-0.275637,tan(254°)=3.487414 sin(255°)=-0.965926,cos(255°)=-0.258819,tan(255°)=3.732051 sin(256°)=-0.970296,cos(256°)=-0.241922,tan(256°)=4.010781 sin(257°)=-0.974370,cos(257°)=-0.224951,tan(257°)=4.331476 sin(258°)=-0.978148,cos(258°)=-0.207912,tan(258°)=4.704630sin(259°)=-0.981627,cos(259°)=-0.190809,tan(259°)=5.144554 sin(260°)=-0.984808,cos(260°)=-0.173648,tan(260°)=5.671282 sin(261°)=-0.987688,cos(261°)=-0.156434,tan(261°)=6.313752 sin(262°)=-0.990268,cos(262°)=-0.139173,tan(262°)=7.115370 sin(263°)=-0.992546,cos(263°)=-0.121869,tan(263°)=8.144346 sin(264°)=-0.994522,cos(264°)=-0.104528,tan(264°)=9.514364 sin(265°)=-0.996195,cos(265°)=-0.087156,tan(265°)=11.430052 sin(266°)=-0.997564,cos(266°)=-0.069756,tan(266°)=14.300666 sin(267°)=-0.998630,cos(267°)=-0.052336,tan(267°)=19.081137 sin(268°)=-0.999391,cos(268°)=-0.034899,tan(268°)=28.636253 sin(269°)=-0.999848,cos(269°)=-0.017452,tan(269°)=57.289962 sin(270°)=-1.000000,cos(270°)=-0.000000,tan(270°)=无意义sin(271°)=-0.999848,cos(271°)=0.017452,tan(271°)=-57.289962sin(272°)=-0.999391,cos(272°)=0.034899,tan(272°)=-28.636253 sin(273°)=-0.998630,cos(273°)=0.052336,tan(273°)=-19.081137 sin(274°)=-0.997564,cos(274°)=0.069756,tan(274°)=-14.300666 sin(275°)=-0.996195,cos(275°)=0.087156,tan(275°)=-11.430052 sin(276°)=-0.994522,cos(276°)=0.104528,tan(276°)=-9.514364 sin(277°)=-0.992546,cos(277°)=0.121869,tan(277°)=-8.144346 sin(278°)=-0.990268,cos(278°)=0.139173,tan(278°)=-7.115370 sin(279°)=-0.987688,cos(279°)=0.156434,tan(279°)=-6.313752 sin(280°)=-0.984808,cos(280°)=0.173648,tan(280°)=-5.671282 sin(281°)=-0.981627,cos(281°)=0.190809,tan(281°)=-5.144554 sin(282°)=-0.978148,cos(282°)=0.207912,tan(282°)=-4.704630 sin(283°)=-0.974370,cos(283°)=0.224951,tan(283°)=-4.331476 sin(284°)=-0.970296,cos(284°)=0.241922,tan(284°)=-4.010781sin(285°)=-0.965926,cos(285°)=0.258819,tan(285°)=-3.732051 sin(286°)=-0.961262,cos(286°)=0.275637,tan(286°)=-3.487414 sin(287°)=-0.956305,cos(287°)=0.292372,tan(287°)=-3.270853 sin(288°)=-0.951057,cos(288°)=0.309017,tan(288°)=-3.077684 sin(289°)=-0.945519,cos(289°)=0.325568,tan(289°)=-2.904211 sin(290°)=-0.939693,cos(290°)=0.342020,tan(290°)=-2.747477 sin(291°)=-0.933580,cos(291°)=0.358368,tan(291°)=-2.605089 sin(292°)=-0.927184,cos(292°)=0.374607,tan(292°)=-2.475087 sin(293°)=-0.920505,cos(293°)=0.390731,tan(293°)=-2.355852 sin(294°)=-0.913545,cos(294°)=0.406737,tan(294°)=-2.246037 sin(295°)=-0.906308,cos(295°)=0.422618,tan(295°)=-2.144507 sin(296°)=-0.898794,cos(296°)=0.438371,tan(296°)=-2.050304 sin(297°)=-0.891007,cos(297°)=0.453990,tan(297°)=-1.962611sin(298°)=-0.882948,cos(298°)=0.469472,tan(298°)=-1.880726 sin(299°)=-0.874620,cos(299°)=0.484810,tan(299°)=-1.804048 sin(300°)=-0.866025,cos(300°)=0.500000,tan(300°)=-1.732051 sin(301°)=-0.857167,cos(301°)=0.515038,tan(301°)=-1.664279 sin(302°)=-0.848048,cos(302°)=0.529919,tan(302°)=-1.600335 sin(303°)=-0.838671,cos(303°)=0.544639,tan(303°)=-1.539865 sin(304°)=-0.829038,cos(304°)=0.559193,tan(304°)=-1.482561 sin(305°)=-0.819152,cos(305°)=0.573576,tan(305°)=-1.428148 sin(306°)=-0.809017,cos(306°)=0.587785,tan(306°)=-1.376382 sin(307°)=-0.798636,cos(307°)=0.601815,tan(307°)=-1.327045 sin(308°)=-0.788011,cos(308°)=0.615661,tan(308°)=-1.279942 sin(309°)=-0.777146,cos(309°)=0.629320,tan(309°)=-1.234897 sin(310°)=-0.766044,cos(310°)=0.642788,tan(310°)=-1.191754sin(311°)=-0.754710,cos(311°)=0.656059,tan(311°)=-1.150368 sin(312°)=-0.743145,cos(312°)=0.669131,tan(312°)=-1.110613 sin(313°)=-0.731354,cos(313°)=0.681998,tan(313°)=-1.072369 sin(314°)=-0.719340,cos(314°)=0.694658,tan(314°)=-1.035530 sin(315°)=-0.707107,cos(315°)=0.707107,tan(315°)=-1.000000 sin(316°)=-0.694658,cos(316°)=0.719340,tan(316°)=-0.965689 sin(317°)=-0.681998,cos(317°)=0.731354,tan(317°)=-0.932515 sin(318°)=-0.669131,cos(318°)=0.743145,tan(318°)=-0.900404 sin(319°)=-0.656059,cos(319°)=0.754710,tan(319°)=-0.869287 sin(320°)=-0.642788,cos(320°)=0.766044,tan(320°)=-0.839100 sin(321°)=-0.629320,cos(321°)=0.777146,tan(321°)=-0.809784 sin(322°)=-0.615661,cos(322°)=0.788011,tan(322°)=-0.781286 sin(323°)=-0.601815,cos(323°)=0.798636,tan(323°)=-0.753554sin(324°)=-0.587785,cos(324°)=0.809017,tan(324°)=-0.726543 sin(325°)=-0.573576,cos(325°)=0.819152,tan(325°)=-0.700208 sin(326°)=-0.559193,cos(326°)=0.829038,tan(326°)=-0.674509 sin(327°)=-0.544639,cos(327°)=0.838671,tan(327°)=-0.649408 sin(328°)=-0.529919,cos(328°)=0.848048,tan(328°)=-0.624869 sin(329°)=-0.515038,cos(329°)=0.857167,tan(329°)=-0.600861 sin(330°)=-0.500000,cos(330°)=0.866025,tan(330°)=-0.577350 sin(331°)=-0.484810,cos(331°)=0.874620,tan(331°)=-0.554309 sin(332°)=-0.469472,cos(332°)=0.882948,tan(332°)=-0.531709 sin(333°)=-0.453990,cos(333°)=0.891007,tan(333°)=-0.509525 sin(334°)=-0.438371,cos(334°)=0.898794,tan(334°)=-0.487733 sin(335°)=-0.422618,cos(335°)=0.906308,tan(335°)=-0.466308 sin(336°)=-0.406737,cos(336°)=0.913545,tan(336°)=-0.445229sin(337°)=-0.390731,cos(337°)=0.920505,tan(337°)=-0.424475 sin(338°)=-0.374607,cos(338°)=0.927184,tan(338°)=-0.404026 sin(339°)=-0.358368,cos(339°)=0.933580,tan(339°)=-0.383864 sin(340°)=-0.342020,cos(340°)=0.939693,tan(340°)=-0.363970 sin(341°)=-0.325568,cos(341°)=0.945519,tan(341°)=-0.344328 sin(342°)=-0.309017,cos(342°)=0.951057,tan(342°)=-0.324920 sin(343°)=-0.292372,cos(343°)=0.956305,tan(343°)=-0.305731 sin(344°)=-0.275637,cos(344°)=0.961262,tan(344°)=-0.286745 sin(345°)=-0.258819,cos(345°)=0.965926,tan(345°)=-0.267949 sin(346°)=-0.241922,cos(346°)=0.970296,tan(346°)=-0.249328 sin(347°)=-0.224951,cos(347°)=0.974370,tan(347°)=-0.230868 sin(348°)=-0.207912,cos(348°)=0.978148,tan(348°)=-0.212557 sin(349°)=-0.190809,cos(349°)=0.981627,tan(349°)=-0.194380sin(350°)=-0.173648,cos(350°)=0.984808,tan(350°)=-0.176327 sin(351°)=-0.156434,cos(351°)=0.987688,tan(351°)=-0.158384 sin(352°)=-0.139173,cos(352°)=0.990268,tan(352°)=-0.140541 sin(353°)=-0.121869,cos(353°)=0.992546,tan(353°)=-0.122785 sin(354°)=-0.104528,cos(354°)=0.994522,tan(354°)=-0.105104 sin(355°)=-0.087156,cos(355°)=0.996195,tan(355°)=-0.087489 sin(356°)=-0.069756,cos(356°)=0.997564,tan(356°)=-0.069927 sin(357°)=-0.052336,cos(357°)=0.998630,tan(357°)=-0.052408 sin(358°)=-0.034899,cos(358°)=0.999391,tan(358°)=-0.034921 sin(359°)=-0.017452,cos(359°)=0.999848,tan(359°)=-0.017455 sin(360°)=-0.000000,cos(360°)=1.000000,tan(360°)=-0.000000。
特殊三角函数值对照表(特殊角的三角函数值)
特殊三角函数值对照表（特殊角的三角函数值）《特殊角的三角函数值》是人教版数学九年级下册第二十八章的内容，特殊三角函数值一般指在0，30°，45°，60°，90°，180°角下的正余弦值。
这些角度的三角函数值是经常用到的。
并且利用两角和与差的三角函数公式，可以求出一些其他角度的三角函数值。
具体的三角函数值如下表：扩展资料：黄金三角函数介绍：α=18°(π/10) sinα=(√5-1)/4 cosα=√(10+2√5)/4tαnα=√(25-10√5)/5cscα=√5+1 secα=√(50-10√5)/5 cotα=√(5+2√5)α=36°(π/5) sinα=√(10-2√5)/4 cosα=(√5+1)/4tαnα=√(5-2√5)cscα=√(50+10√5)/5 secα=√5-1 cotα=√(25+10√5)/5α=54°(3π/10) sinα=(√5+1)/4 cosα=√(10-2√5)/4 tαnα=√(25+10√5)/5是数学中属于初等函数中的超越函数的一类函数。
它们的本质是任意角的集合与一个比值的集合的变量之间的映射。
通常的三角函数是在平面直角坐标系中定义的，其定义域为整个实数域。
另一种定义是在直角三角形中，但并不完全。
扩展资料：三角函数在复数中有重要的应用。
三角函数也是物理学中的常用工具。
它有六种基本函数函数名正弦余弦正切余切正割余割符号 sin cos tan cot sec csc正弦函数sin（A）=a/c余弦函数cos（A）=b/c正切函数tan（A）=a/b余切函数cot（A）=b/a其中a为对边，b为邻边，c为斜边特殊角的值如下表：在直角三角形中，任意一锐角∠A的对边与斜边的比叫做∠A 的正弦，记作sinA（由英语sine一词简写得来），即sinA=∠A的对边/斜边。
扩展资料：sinα = tanα × cosα（即sinα / cosα = tanα ）cosα = cotα × sinα （即cosα / sinα = cotα）tanα = sinα × secα (即tanα / sinα = secα)sin ( α ± β ) = sinα · cosβ ± cosα · sinβsin ( α + β + γ ) = sinα · cosβ · cosγ +cosα · sinβ · cosγ + cosα · cosβ · sinγ - sinα · sinβ · sinγcos ( α ± β ) = cosα cosβ ∓ sinβ sinαtan ( α ± β ) = ( tanα ± tanβ ) / ( 1 ∓ tanα tanβ )完整初中三角函数值表如下图所示：常见的三角函数有正弦函数、余弦函数和正切函数。
三角函数特殊角值表
只想上传这一个表 下面的都是无用的话 不必看了.
1.图示法：借助于下面三个图形来记忆,即使有所遗忘也可依据图形从新推出：
sin30°=cos60°=2
1
sin45°=cos45°=
22
3
解释：正弦值随角度变更,即0˚ 30˚ 45˚ 60˚ 90˚变更;值从0
1
变更,其余相似记忆．
3.纪律记忆法：不雅察表中的数值特点,可总结为下列记忆纪
律：
① 有界性：（锐角三角函数值都是正值）即当
0°＜α＜90°时,
则0＜sin α＜1; 0＜cos α＜1 ; tan α＞0 ; cot α＞0. ②增减性：（锐角的正弦.正切值随角度的增大而增大;余弦.余切值随角度的增大而减小）,即当0＜A ＜B ＜90°时,则sin A ＜sin B ;tan A ＜tan B ; cos A ＞cos B ;cot A ＞cot B ;特殊地：若0°＜α＜45°,则sin A ＜cos A ;tan A ＜cot A
若45°＜A ＜90°,则sin A ＞cos A ;tan A ＞cot A ． 4.口决记忆法：不雅察表中的数值特点 正弦.余弦值可暗示为
2
m 情势,正切.余切值可暗示为
3
m 情势,有
关m 的值可归纳成顺口溜：一.二.三;三.二.一;三九二十七．。
三角函数表
三角函数表
在数学领域中，三角函数是一类描述角和三角形边之间关系的函数。
主要有正
弦函数、余弦函数和正切函数等。
这些函数在数学和物理学中扮演着重要的角色，广泛应用于各种领域中。
下面是三角函数表，列出了各角度下正弦、余弦和正切的数值：
角度（°）正弦值余弦值正切值
0 0 1 0
30 0.5 0.866 0.577
45 0.707 0.707 1
60 0.866 0.5 1.732
90 1 0 无穷大
除了上表中列举的角度外，三角函数在整个数轴上都有定义。
在单位圆中，三
角函数的定义与三角形的三个边的比例有关。
正弦函数代表了对边与斜边的比值，余弦函数代表了邻边与斜边的比值，而正切函数代表了对边与邻边的比值。
三角函数在解决三角形相关问题、波动问题等方面有着广泛应用。
在物理学中，三角函数也经常出现，比如在描述波动、振动等现象时，三角函数是不可或缺的工具。
总的来说，三角函数是数学中的一大重要概念，深入理解三角函数将有助于我
们更好地理解和应用数学知识，进而解决实际问题。
希望通过这份三角函数表，读者能对三角函数有更清晰的认识。
三角函数值表及记忆方法
只想上传这一个表 下面的都就是无用的话 不用瞧了。
1、图示法:借助于下面三个图形来记忆,即使有所遗忘也可根据图形重新推出: sin30°=cos60°=
2
1
sin45°=cos45°=22
2 30˚ 45˚ 60˚ 90˚
23 1变化,其余类似记忆.
3、口决记忆法:观察表中的数值特征 正弦、余弦值可表示为
2m 形式,正切、余切值可表示为3
m
形式,有关m 的值可归纳成顺口溜:一、二、三;三、二、一;三九二十七.
4、规律记忆法:观察表中的数值特征,可总结为下列记忆规律: ① 有界性:(锐角三角函数值都就是正值)即当0°＜α＜90°时,
则0＜sin α＜1; 0＜cos α＜1 ; tan α＞0 ; cot α＞0。
②增减性:(锐角的正弦、正切值随角度的增大而增大;余弦、余切值随角度的增大而减小),即当0＜A ＜B ＜90°时,则sin A ＜sin B ;tan A ＜tan B ; cos A ＞cos B ;cot A ＞cot B ;特别地:若0°＜α＜45°,则sin A ＜cos A ;tan A ＜cot A 若45°＜A ＜90°,则sin A ＞cos A ;tan A ＞cot A .。
三角函数值表
三角函数值表三角函数值定义三角函数是数学中属于初等函数中的超越函数的一类函数。
它们的本质是任意角的集合与一个比值的集合的变量之间的映射。
通常的三角函数是在平面直角坐标系中定义的，其定义域为整个实数域。
另一种定义是在直角三角形中，但并不完全。
现代数学把它们描述成无穷数列的极限和微分方程的解，将其定义扩展到复数系。
由于三角函数的周期性，它并不具有单值函数意义上的反函数。
数值表数学方程式数关系tanα·cotα=1sinα·cscα=1cosα·secα=1商的关系tanα=sinα/cosαcotα=cosα/sinα平方关系sinα²+cosα²=11+tanα²=secα²1+cotα²=cscα²以下关系，函数名不变，符号看象限. sin(2kπ+α)=sinαcos(2kπ+α)=cosαtan(2kπ+α)=tanαcot(2kπ+α)=cotαsin(π+α)=-sinαcos(π+α)=-cosαtan(π+α)=tanαcot(π+α)=cotαsin(π-α)=sinαcos(π-α)=-cosαtan(π-α)=-tanαcot(π-α)=-cotαsin(2π-α)=-sinαcos(2π-α)=cosαtan(2π-α)=-tanαcot(2π-α)=-cotα以下关系，奇变偶不变，符号看象限sin(90°-α)=cosαcos(90°-α)=sinαtan(90°-α)=cotαcot(90°-α)=tanαsin(90°+α)=cosαcos(90°+α)=-sinαtan(90°+α)=-cotαcot(90°+α)=-tanαsin(270°-α)=-cosαcos(270°-α)=-sinαtan(270°-α)=cotαcot(270°-α)=tanαsin(270°+α)=-cosαcos(270°+α)=sinαtan(270°+α)=-cotαcot(270°+α)=-tanα积化合差公式sinα·cosβ=(1/2)*[sin(α+β)+sin(α-β)] cosα·sinβ=(1/2)*[sin(α+β)-sin(α-β)] cosα·cosβ=(1/2)*[cos(α+β)+cos(α-β)]sinα·sinβ=-(1/2)*[cos(α+β)-cos(α-β)]和差化积公式sinα+sinβ=2sin[(α+β)/2]·cos[(α-β)/2]sinα-sinβ=2cos[(α+β)/2]·sin[(α-β)/2]cosα+cosβ=2cos[(α+β)/2]·cos[(α-β)/2]cosα-cosβ=-2sin[(α+β)/2]·sin[(α-β)/2]三倍角公式sin3α=3sinα-4sinα³cos3α=4cosα³-3cosα两角和与差的三角函数关系sin(α+β)=sinαcosβ+cosαsinβsin(α-β)=sinαcosβ-cosαsinβcos(α+β)=cosαcosβ-sinαsinβcos(α-β)=cosαcosβ+sinαsinβtan(α+β)=(tanα+tanβ)/(1-tanα·tanβ)tan(α-β)=(tanα-tanβ)/(1+tanα·tanβ)正弦二倍角公式sin2α= 2cosαsinα推导:sin2A=sin(A+A)=sinAcosA+cosAsinA=2sinAcosA拓展公式:sin2A=2sinAcosA=2tanAcos2A=2tanA/[1+tan2A] 1+sin2A=(sinA+cosA)^2余弦二倍角公式余弦二倍角公式有三组表示形式，三组形式等价:1.Cos2a=Cos2a-Sin2a=[1-tan2a]/[1+tan2a]2.Cos2a=1-2Sin2a3.Cos2a=2Cos2a-1推导:cos2A=cos(A+A)=cosAcosA-sinAsinA=cos2A-sin2A=2cos2 A-1=1-2sin2A正切二倍角公式tan2α=2tanα/[1-tan2α]推导:tan2A=tan(A+A)=(tanA+tanA)/(1-tanAtanA)=2tanA/[1-tan 2A]降幂公式cosA^2=[1+cos2A]/2sinA^2=[1-cos2A]/2tanA^2=[1-cos2A]/[1+cos2A]变式:sin2α=sin^2(α+π/4)-cos^2(α+π/4)=2sin^2(a+π/4)-1=1-2cos^2(α+π/4); cos2α=2sin(α+π/4)cos(α+π/4)余弦定理:a^2=b^2+c²-2bc cosAb^2=c^2+a^2-2ca cosB c^2=a^2+b^2-2ab cosC。
三角函数特殊角值表
角度 函数 0 30 45 60 90 120 135 150 180 270 360 角a 的弧度0 π/6 π/4 π/3 π/2 2π/3 3π/4 5π/6 π 3π/2 2π sin 0 1/2 √2/2 √3/2 1 √3/2 √2/2 1/2 0 -1 0 cos 1 √3/2 √2/2 1/2 0 -1/2 -√2/2 -√3/2 -1 0 1 tan√3/31√3-√3-1-√3/31、图示法：借助于下面三个图形来记忆，即使有所遗忘也可根据图形重新推出： sin30°=cos60°=21，sin45°=cos45°=22， tan30°=cot60°=33， tan 45°=cot45°=1正弦函数 sinθ=y/r 余弦函数 cosθ=x/r 正切函数 tanθ=y/x 余切函数 cotθ=x/y 正割函数 secθ=r/x 余割函数 cscθ=r/y2、列表法：说明：正弦值随角度变化，即0˚ 30˚ 45˚ 60˚ 90˚变化；值从02122 23 1变化，其余类似记忆．3、规律记忆法：观察表中的数值特征，可总结为下列记忆规律：① 有界性：（锐角三角函数值都是正值）即当0°＜α＜90°时，则0＜sin α＜1； 0＜cos α＜1 ； tan α＞0 ； cot α＞0。
②增减性：（锐角的正弦、正切值随角度的增大而增大；余弦、余切值随角度的增大而减小），即当0＜A ＜B ＜90°时，则sin A ＜sin B ；tan A ＜tan B ； cos A ＞cos B ；cot A ＞cot B ；特别地：若0°＜α＜45°，则sin A ＜cos A ；tan A ＜cot A 若45°＜A ＜90°，则sin A ＞cos A ；tan A ＞cot A ． 4、口决记忆法：观察表中的数值特征 正弦、余弦值可表示为2m 形式，正切、余切值可表示为3m 形式，有关m 的值可归纳成顺口溜：一、二、三；三、二、一；三九二十七．30˚ 123145˚ 1212 60˚ 3函数名正弦余弦正切余切正割余割符号sin cos tan cot sec csc正弦函数sin（A）=a/c余弦函数cos（A）=b/c正切函数tan（A）=a/b余切函数cot（A）=b/a其中a为对边，b为邻边，c为斜边三角函数对照表三角函数SIN COS TAN 三角函数SIN COS TAN 0°0 1 0 90° 1 0 无1°0.0174 0.9998 0.0174 89°0.9998 0.0174 57.2899 2°0.0348 0.9993 0.0349 88°0.9993 0.0348 28.6362 3°0.0523 0.9986 0.0524 87°0.9986 0.0523 19.0811 4°0.0697 0.9975 0.0699 86°0.9975 0.0697 14.3006 5°0.0871 0.9961 0.0874 85°0.9961 0.0871 11.4300 6°0.1045 0.9945 0.1051 84°0.9945 0.1045 9.5143 7°0.1218 0.9925 0.1227 83°0.9925 0.1218 8.1443 8°0.1391 0.9902 0.1405 82°0.9902 0.1391 7.1153 9°0.1564 0.9876 0.1583 81°0.9876 0.1564 6.3137 10°0.1736 0.9848 0.1763 80°0.9848 0.1736 5.6712 11°0.1908 0.9816 0.1943 79°0.9816 0.1908 5.1445 12°0.2079 0.9781 0.2125 78°0.9781 0.2079 4.7046 13°0.2249 0.9743 0.2308 77°0.9743 0.2249 4.3314 14°0.2419 0.9702 0.2493 76°0.9702 0.2419 4.0107 15°0.2588 0.9659 0.2679 75°0.9659 0.2588 3.7320二倍角的正弦、余弦和正切公式三倍角的正弦、余弦和正切公式sin 22sin cos cos 2cos 2sin 22cos 2112sin 2αααααααα==-=-=-2tan tan 21tan 2ααα=--sin 33sin 4sin 3cos34cos33cos .3tan tan 3tan 313tan 2αααααααααα=-=--=--三角函数的和差化积公式 三角函数的积化和差公式sin sin 2sincos 22sin sin 2cos sin22cos cos 2cos cos22cos cos 2sin sin22αβαβαβαβαβαβαβαβαβαβαβαβ+-+=⋅+--=⋅+-+=⋅+--=-⋅[][][][]1sin cos sin()sin()21cos sin sin()sin()21cos cos cos()cos()21sin sin cos()cos()2αβαβαβαβαβαβαβαβαβαβαβαβ⋅=++-⋅=+--⋅=++-⋅=-+--化asinα ±bcosα为一个角的一个三角函数的形式（辅助角的三角函数的公式）22sin cos sin()a x b x a b x φ±=+±其中φ角所在的象限由a 、b 的符号确定，φ角的值由tan ba φ=确定六边形记忆法：图形结构“上弦中切下割，左正右余中间1”；记忆方法“对角线上两个函数的积为1；阴影三角形上两顶点的三角函数值的平方和等于下顶点的三角函数值的平方；任意一顶点的三角函数值等于相邻两个顶点的三角函数值的乘积。