最常用三角函数值盘点

利用特殊角的三角函数值去求未知角的三角函数是大学联考中常见题型，本文是小编整理最常用三角函数值的资料，仅供参考。

特殊角的三角函数

角度a 0° 30° 45° 60° 90° 120° 180°

0 1/2 √2/2 √3/2 1 √3/2 0

1 √3/2 √2/2 1/2 0 -1/2 -1

0 √3/3 1 √3 无限大 -√3 0

/ √3 1 √3/3 0 -√3/3 /

函数名 正弦 余弦 正切 余切 正割 余割

在平面直角坐标系xOy中，从点O引出一条射线OP，设旋转角为θ，设OP=r，P点的坐标为(x，y)有

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/y

正弦(sin):角α的对边比上斜边

余弦(cos):角α的邻边比上斜边

正切(tan):角α的对边比上邻边

余切(cot):角α的邻边比上对边

正割(sec):角α的斜边比上邻边

余割(csc):角α的斜边比上对边

(1)特殊角三角函数值

sin0=0

sin30=0.5

sin45=0.7071 二分之根号2

sin60=0.8660 二分之根号3

sin90=1

cos0=1

cos30=0.866025404 二分之根号3

cos45=0.707106781 二分之根号2

cos60=0.5

cos90=0

tan0=0

tan30=0.577350269 三分之根号3

tan45=1

tan60=1.732050808 根号3

tan90=无

cot0=无

cot30=1.732050808 根号3

cot45=1

cot60=0.577350269 三分之根号3

cot90=0

(2)0°~90°的任意角的三角函数值，查三角函数表。(见下)

(3)锐角三角函数值的变化情况

(i)锐角三角函数值都是正值

(ii)当角度在0°~90°间变化时，

正弦值随着角度的增大(或减小)而增大(或减小)

余弦值随着角度的增大(或减小)而减小(或增大)

正切值随着角度的增大(或减小)而增大(或减小)

余切值随着角度的增大(或减小)而减小(或增大)

(iii)当角度在0°≤α≤90°间变化时，

0≤sinα≤1, 1≥cosα≥0,

当角度在0°<α<90°间变化时，

tanα>0, cotα>0.

“锐角三角函数”属于三角学，是《数学课程标准》中“空间与图形”领域的重要内容。从《数学课程标准》看，中学数学把三角学内容分成两个部分，第一部分放在义务教育第三学段，第二部分放在高中阶段。在义务教育第三学段，主要研究锐角三角函数和解直角三角形的内容，本套教科书安排了一章的.内容，就是本章“锐角三角函数”。在高中阶段的三角内容是三角学的主体部分，包括解斜三角形、三角函数、反三角函数和简单的三角方程。无论是从内容上看，还是从思考问题的方法上看，前一部分都是后一部分的重要基础，掌握锐角三角函数的概念和解直角三角形的方法，是学习三角函数和解斜三角形的重要准备。

sin0=0,

sin15=(√6-√2)/4 ,

sin30=1/2,

sin45=√2/2,

sin60=√3/2,

sin75=(√6+√2)/2 ,

sin90=1,

sin105=√2/2*(√3/2+1/2)

sin120=√3/2

sin135=√2/2

sin150=1/2

sin165=(√6-√2)/4

sin180=0

sin270=-1

sin360=0

sin1=0.01745240643728351 sin2=0.03489949670250097 sin3=0.05233595624294383

sin4=0.0697564737441253 sin5=0.08715574274765816 sin6=0.10452846326765346

sin7=0.12186934340514747 sin8=0.13917310096006544 sin9=0.15643446504023087

sin10=0.17364817766693033 sin11=0.1908089953765448 sin12=0.20791169081775931

sin13=0.22495105434386497 sin14=0.24192189559966773 sin15=0.25881904510252074

sin16=0.27563735581699916 sin17=0.2923717047227367 sin18=0.3090169943749474

sin19=0.3255681544571567 sin20=0.3420201433256687 sin21=0.35836794954530027

sin22=0.374606593415912 sin23=0.3907311284892737 sin24=0.40673664307580015

sin25=0.42261826174069944 sin26=0.4383711467890774 sin27=0.45399049973954675

sin28=0.4694715627858908 sin29=0.48480962024633706 sin30=0.49999999999999994

sin31=0.5150380749100542 sin32=0.5299192642332049 sin33=0.544639035015027

sin34=0.5591929034707468 sin35=0.573576436351046 sin36=0.5877852522924731

sin37=0.6018150231520483 sin38=0.6156614753256583 sin39=0.6293203910498375

sin40=0.6427876096865392 sin41=0.6560590289905073 sin42=0.6691306063588582

sin43=0.6819983600624985 sin44=0.6946583704589972 sin45=0.7071067811865475

sin46=0.7193398003386511 sin47=0.7313537016191705 sin48=0.7431448254773941

sin49=0.7547095802227719 sin50=0.766044443118978 sin51=0.7771459614569708

sin52=0.7880107536067219 sin53=0.7986355100472928 sin54=0.8090169943749474

sin55=0.8191520442889918 sin56=0.8290375725550417 sin57=0.8386705679454239

sin58=0.848048096156426 sin59=0.8571673007021122 sin60=0.8660254037844386

sin61=0.8746197071393957 sin62=0.8829475928589269 sin63=0.8910065241883678

sin64=0.898794046299167 sin65=0.9063077870366499 sin66=0.9135454576426009

sin67=0.9205048534524404 sin68=0.9271838545667873 sin69=0.9335804264972017

sin70=0.9396926207859083 sin71=0.9455185755993167 sin72=0.9510565162951535

sin73=0.9563047559630354 sin74=0.9612616959383189 sin75=0.9659258262890683

sin76=0.9702957262759965 sin77=0.9743700647852352 sin78=0.9781476007338057

sin79=0.981627183447664 sin80=0.984807753012208 sin81=0.9876883405951378

sin82=0.9902680687415704 sin83=0.992546151641322 sin84=0.9945218953682733

sin85=0.9961946980917455 sin86=0.9975640502598242 sin87=0.9986295347545738

sin88=0.9993908270190958 sin89=0.9998476951563913

sin90=1

cos1=0.9998476951563913 cos2=0.9993908270190958 cos3=0.9986295347545738

cos4=0.9975640502598242 cos5=0.9961946980917455 cos6=0.9945218953682733

cos7=0.992546151641322 cos8=0.9902680687415704 cos9=0.9876883405951378

cos10=0.984807753012208 cos11=0.981627183447664 cos12=0.9781476007338057

cos13=0.9743700647852352 cos14=0.9702957262759965 cos15=0.9659258262890683

cos16=0.9612616959383189 cos17=0.9563047559630355 cos18=0.9510565162951535

cos19=0.9455185755993168 cos20=0.9396926207859084 cos21=0.9335804264972017

cos22=0.9271838545667874 cos23=0.9205048534524404 cos24=0.9135454576426009

cos25=0.9063077870366499 cos26=0.898794046299167 cos27=0.8910065241883679

cos28=0.882947592858927 cos29=0.8746197071393957 cos30=0.8660254037844387

cos31=0.8571673007021123 cos32=0.848048096156426 cos33=0.838670567945424

cos34=0.8290375725550417 cos35=0.8191520442889918 cos36=0.8090169943749474

cos37=0.7986355100472928 cos38=0.7880107536067219 cos39=0.7771459614569709

cos40=0.766044443118978 cos41=0.754709580222772 cos42=0.7431448254773942

cos43=0.7313537016191705 cos44=0.7193398003386512 cos45=0.7071067811865476

cos46=0.6946583704589974 cos47=0.6819983600624985 cos48=0.6691306063588582

cos49=0.6560590289905074 cos50=0.6427876096865394 cos51=0.6293203910498375

cos52=0.6156614753256583 cos53=0.6018150231520484 cos54=0.5877852522924731

cos55=0.5735764363510462 cos56=0.5591929034707468 cos57=0.5446390350150272

cos58=0.5299192642332049 cos59=0.5150380749100544 cos60=0.5000000000000001

cos61=0.4848096202463371 cos62=0.46947156278589086 cos63=0.4539904997395468

cos64=0.43837114678907746 cos65=0.42261826174069944 cos66=0.4067366430758004

cos67=0.3907311284892737 cos68=0.3746065934159122 cos69=0.35836794954530015

cos70=0.3420201433256688 cos71=0.32556815445715675 cos72=0.30901699437494745

cos73=0.29237170472273677 cos74=0.27563735581699916 cos75=0.25881904510252074

cos76=0.24192189559966767 cos77=0.22495105434386514 cos78=0.20791169081775923

cos79=0.19080899537654491 cos80=0.17364817766693041 cos81=0.15643446504023092

cos82=0.13917310096006546 cos83=0.12186934340514749 cos84=0.10452846326765346

cos85=0.08715574274765836 cos86=0.06975647374412523 cos87=0.052335956242943966

cos88=0.03489949670250108 cos89=0.0174524064372836

cos90=0

tan1=0.017455064928217585 tan2=0.03492076949174773 tan3=0.052407779283041196

tan4=0.06992681194351041 tan5=0.08748866352592401 tan6=0.10510423526567646

tan7=0.1227845609029046 tan8=0.14054083470239145 tan9=0.15838444032453627

tan10=0.17632698070846497 tan11=0.19438030913771848 tan12=0.2125565616700221

tan13=0.2308681911255631 tan14=0.24932800284318068 tan15=0.2679491924311227

tan16=0.2867453857588079 tan17=0.30573068145866033 tan18=0.3249196962329063

tan19=0.34432761328966527 tan20=0.36397023426620234 tan21=0.3838640350354158

tan22=0.4040262258351568 tan23=0.4244748162096047 tan24=0.4452286853085361

tan25=0.4663076581549986 tan26=0.4877325885658614 tan27=0.5095254494944288

tan28=0.5317094316614788 tan29=0.554309051452769 tan30=0.5773502691896257

tan31=0.6008606190275604 tan32=0.6248693519093275 tan33=0.6494075931975104

tan34=0.6745085168424265 tan35=0.7002075382097097 tan36=0.7265425280053609

tan37=0.7535540501027942 tan38=0.7812856265067174 tan39=0.8097840331950072

tan40=0.8390996311772799 tan41=0.8692867378162267 tan42=0.9004040442978399

tan43=0.9325150861376618 tan44=0.9656887748070739 tan45=0.9999999999999999

tan46=1.0355303137905693 tan47=1.0723687100246826 tan48=1.1106125148291927

tan49=1.1503684072210092 tan50=1.19175359259421 tan51=1.234897156535051

tan52=1.2799416321930785 tan53=1.3270448216204098 tan54=1.3763819204711733

tan55=1.4281480067421144 tan56=1.4825609685127403 tan57=1.5398649638145827

tan58=1.6003345290410506 tan59=1.6642794823505173 tan60=1.7320508075688767

tan61=1.8040477552714235 tan62=1.8807264653463318 tan63=1.9626105055051503

tan64=2.050303841579296 tan65=2.1445069205095586 tan66=2.246036773904215

tan67=2.355852365823753 tan68=2.4750868534162946 tan69=2.6050890646938023

tan70=2.7474774194546216 tan71=2.904210877675822 tan72=3.0776835371752526

tan73=3.2708526184841404 tan74=3.4874144438409087 tan75=3.7320508075688776

tan76=4.0107809335358455 tan77=4.331475874284153 tan78=4.704630109478456

tan79=5.144554015970307 tan80=5.671281819617707 tan81=6.313751514675041

tan82=7.115369722384207 tan83=8.144346427974593 tan84=9.514364454222587

tan85=11.43005230276132 tan86=14.300666256711942 tan87=19.08113668772816

tan88=28.636253282915515 tan89=57.289961630759144

tan90=无取值