求210度的正弦值和余弦值？

sin210°=sin(180°+30°)=-sin30°=-1/2

cos210°的三角函数值 cos1109°的三角函数值

cos210°的三角函数值 cos1109°的三角函数值

cos210°=cos（180°+30°）=-cos30°=-（根号3）/2

如果帮到你，请记得采纳，O(∩_∩)O谢谢

sin210= -sin(210-180) = -sin30= -1/2

cos210= -cos(210-180) = -cos30= -√3/2

祝你学习进步，更上一层楼！ (^__^)

sin210°=sin(180°+30°）=-sin30°=-1/2

cos210°=cos(180°+30°）=-cos30°=-√3/2

祝你好运

sin210°=-sin30°=-1/2

cos210°=-cos30°=-√3/2

sin210=-sin30=-1/2

cos210=-cos30=-√3/2

三角函数值列个表给我。。谢

上面是废话..表看 给你两个表，个是5°至360°每隔5°的角的正弦、余弦、正切、余切函数的高精度近似值。

第二个是0°、15°、18°、30°、36°、45°、54°、60°、72°、75°、90°这些角的正弦、余弦、正切函数值的数学表达式。其他角的三角函数值的数学表达式一般极其复杂，故未收录。90°以上角的三角函数可借助此表用诱导公式求出。

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以下是个表：

sin5° = 0.0871557427476582; cos5° = 0.9961946980746;

tan5° = 0.087488663525924; cot5° = 11.4300523027613;

sin10° = 0.17364817766693; cos10° = 0.984807753012208;

tan10° = 0.176326980708465; cot10° = 5.67128181961771;

sin15° = 0.258819045102521; cos15° = 0.965925826289068;

tan15° = 0.2679492431123; cot15° = 3.73205080756888;

sin20° = 0.342020143325669; cos20° = 0.939692620785908;

tan20° = 0.363970234266202; cot20° = 2.74747741945462;

sin25° = 0.422618261740699; cos25° = 0.90630778703665;

tan25° = 0.466307658154999; cot25° = 2.14450692050956;

sin30° = 0.5; cos30° = 0.866025403784439;

tan30° = 0.5773502689626; cot30° = 1.73205080756888;

sin35° = 0.573576436351046; cos35° = 0.8152044288992;

tan35° = 0.70020753820971; cot35° = 1.42814800674211;

sin40° = 0.642787609686539; cos40° = 0.766044443118978;

tan40° = 0.83909963117728; cot40° = 1.175359259421;

sin45° = 0.707106781186547; cos45° = 0.707106781186548;

tan45° = 1; cot45° = 1;

sin50° = 0.766044443118978; cos50° = 0.642787609686539;

tan50° = 1.175359259421; cot50° = 0.83909963117728;

sin55° = 0.8152044288992; cos55° = 0.573576436351046;

tan55° = 1.42814800674211; cot55° = 0.70020753820971;

sin60° = 0.866025403784439; cos60° = 0.5;

tan60° = 1.73205080756888; cot60° = 0.5773502689626;

sin65° = 0.90630778703665; cos65° = 0.422618261740699;

tan65° = 2.14450692050956; cot65° = 0.466307658154999;

sin70° = 0.939692620785908; cos70° = 0.342020143325669;

tan70° = 2.74747741945462; cot70° = 0.363970234266202;

sin75° = 0.965925826289068; cos75° = 0.258819045102521;

tan75° = 3.73205080756888; cot75° = 0.2679492431123;

sin80° = 0.984807753012208; cos80° = 0.17364817766693;

tan80° = 5.67128181961771; cot80° = 0.176326980708465;

sin85° = 0.9961946980746; cos85° = 0.0871557427476584;

tan85° = 11.4300523027613; cot85° = 0.0874886635259242;

sin90° = 1; cos90° = 0;

tan90° = ∞; cot90° = 0;

sin95° = 0.9961946980746; cos95° = -0.0871557427476582;

tan95° = -11.4300523027613; cot95° = -0.0874886635259241;

sin100° = 0.984807753012208; cos100° = -0.17364817766693;

tan100° = -5.67128181961771; cot100° = -0.176326980708465;

sin105° = 0.965925826289068; cos105° = -0.258819045102521;

tan105° = -3.73205080756888; cot105° = -0.2679492431123;

sin110° = 0.939692620785908; cos110° = -0.342020143325669;

tan110° = -2.74747741945462; cot110° = -0.363970234266202;

sin115° = 0.90630778703665; cos115° = -0.422618261740699;

tan115° = -2.14450692050956; cot115° = -0.466307658154998;

sin120° = 0.866025403784439; cos120° = -0.5;

tan120° = -1.73205080756888; cot120° = -0.5773502689625;

sin125° = 0.8152044288992; cos125° = -0.573576436351046;

tan125° = -1.42814800674212; cot125° = -0.700207538209709;

sin130° = 0.766044443118978; cos130° = -0.642787609686539;

tan130° = -1.175359259421; cot130° = -0.83909963117728;

sin135° = 0.707106781186548; cos135° = -0.707106781186547;

tan135° = -1; cot135° = -1;

sin140° = 0.642787609686539; cos140° = -0.766044443118978;

tan140° = -0.83909963117728; cot140° = -1.175359259421;

sin145° = 0.573576436351046; cos145° = -0.8152044288992;

tan145° = -0.70020753820971; cot145° = -1.42814800674211;

sin150° = 0.5; cos150° = -0.866025403784439;

tan150° = -0.5773502689626; cot150° = -1.73205080756888;

sin155° = 0.4226182617407; cos155° = -0.90630778703665;

tan155° = -0.466307658154999; cot155° = -2.14450692050956;

sin160° = 0.342020143325669; cos160° = -0.939692620785908;

tan160° = -0.363970234266203; cot160° = -2.74747741945462;

sin165° = 0.258819045102521; cos165° = -0.965925826289068;

tan165° = -0.2679492431123; cot165° = -3.73205080756887;

sin170° = 0.173648177666931; cos170° = -0.984807753012208;

tan170° = -0.176326980708465; cot170° = -5.6712818196177;

sin175° = 0.0871557427476582; cos175° = -0.9961946980746;

tan175° = -0.087488663525924; cot175° = -11.4300523027613;

sin180° = 0; cos180° = -1;

tan180° = 0; cot180° = ∞;

sin185° = -0.0871557427476579; cos185° = -0.9961946980746;

tan185° = 0.0874886635259238; cot185° = 11.4300523027614;

sin190° = -0.17364817766693; cos190° = -0.984807753012208;

tan190° = 0.176326980708465; cot190° = 5.67128181961771;

sin195° = -0.25881904510252; cos195° = -0.965925826289068;

tan195° = 0.2679492431122; cot195° = 3.73205080756888;

sin200° = -0.342020143325669; cos200° = -0.939692620785908;

tan200° = 0.363970234266202; cot200° = 2.74747741945462;

sin205° = -0.422618261740699; cos205° = -0.90630778703665;

tan205° = 0.466307658154998; cot205° = 2.14450692050956;

sin210° = -0.5; cos210° = -0.866025403784439;

tan210° = 0.5773502689626; cot210° = 1.73205080756888;

sin215° = -0.573576436351046; cos215° = -0.8152044288992;

tan215° = 0.700207538209709; cot215° = 1.42814800674212;

sin220° = -0.642787609686539; cos220° = -0.766044443118978;

tan220° = 0.83909963117728; cot220° = 1.175359259421;

sin225° = -0.707106781186547; cos225° = -0.707106781186548;

tan225° = 1; cot225° = 1;

sin230° = -0.766044443118978; cos230° = -0.642787609686539;

tan230° = 1.175359259421; cot230° = 0.83909963117728;

sin235° = -0.8152044288992; cos235° = -0.573576436351046;

tan235° = 1.42814800674211; cot235° = 0.70020753820971;

sin240° = -0.866025403784438; cos240° = -0.5;

tan240° = 1.73205080756888; cot240° = 0.5773502689626;

sin245° = -0.90630778703665; cos245° = -0.422618261740699;

tan245° = 2.14450692050956; cot245° = 0.466307658154998;

sin° = -0.939692620785908; cos° = -0.342020143325669;

tan° = 2.74747741945462; cot° = 0.363970234266203;

sin255° = -0.965925826289068; cos255° = -0.258819045102521;

tan255° = 3.73205080756888; cot255° = 0.2679492431123;

sin260° = -0.984807753012208; cos260° = -0.17364817766693;

tan260° = 5.67128181961771; cot260° = 0.176326980708465;

sin265° = -0.9961946980746; cos265° = -0.0871557427476582;

tan265° = 11.4300523027613; cot265° = 0.0874886635259241;

sin270° = -1; cos270° = 0;

tan270° = ∞; cot270° = 0;

sin275° = -0.9961946980746; cos275° = 0.0871557427476579;

tan275° = -11.4300523027614; cot275° = -0.0874886635259237;

sin280° = -0.984807753012208; cos280° = 0.17364817766693;

tan280° = -5.67128181961772; cot280° = -0.176326980708465;

sin285° = -0.965925826289068; cos285° = 0.25881904510252;

tan285° = -3.73205080756888; cot285° = -0.2679492431122;

sin290° = -0.939692620785908; cos290° = 0.342020143325669;

tan290° = -2.74747741945462; cot290° = -0.363970234266203;

sin295° = -0.90630778703665; cos295° = 0.422618261740699;

tan295° = -2.14450692050956; cot295° = -0.466307658154998;

sin300° = -0.866025403784439; cos300° = 0.5;

tan300° = -1.73205080756888; cot300° = -0.5773502689626;

sin305° = -0.8152044288992; cos305° = 0.573576436351046;

tan305° = -1.42814800674211; cot305° = -0.70020753820971;

sin310° = -0.766044443118978; cos310° = 0.642787609686539;

tan310° = -1.175359259421; cot310° = -0.83909963117728;

sin315° = -0.707106781186548; cos315° = 0.707106781186547;

tan315° = -1; cot315° = -1;

sin320° = -0.64278760968654; cos320° = 0.766044443118978;

tan320° = -0.839099631177281; cot320° = -1.175359259421;

sin325° = -0.573576436351046; cos325° = 0.8152044288992;

tan325° = -0.70020753820971; cot325° = -1.42814800674211;

sin330° = -0.5; cos330° = 0.866025403784438;

tan330° = -0.5773502689627; cot330° = -1.73205080756887;

sin335° = -0.422618261740699; cos335° = 0.90630778703665;

tan335° = -0.466307658154998; cot335° = -2.14450692050956;

sin340° = -0.342020143325669; cos340° = 0.939692620785908;

tan340° = -0.363970234266203; cot340° = -2.74747741945462;

sin345° = -0.258819045102521; cos345° = 0.965925826289068;

tan345° = -0.2679492431123; cot345° = -3.73205080756888;

sin350° = -0.17364817766693; cos350° = 0.984807753012208;

tan350° = -0.176326980708465; cot350° = -5.67128181961771;

sin355° = -0.0871557427476583; cos355° = 0.9961946980746;

tan355° = -0.0874886635259241; cot355° = -11.4300523027613;

sin360° = 0; cos360° = 1;

tan360° = 0; cot360° = ∞;

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关于第二个表的注释：

“sqrt(x)”表示x的算术平方根，“/”表示除号。

以下是第二个表：

sin0° = 0; cos0° = 1; tan0° = ∞;

sin15° = [sqrt(6)-sqrt(2)]/4; cos15° = [sqrt(6)+sqrt(2)]/4;

tan15° = 2-sqrt(3);

sin18° = [sqrt(5)-1]/4; cos18° = sqrt[10+2sqrt(5)]/4;

tan18° = {3sqrt[50+10sqrt(5)]-5sqrt[10+2sqrt(5)]}/20;

sin30° = 1/2; cos30° = sqrt(3)/2;

tan30° = sqrt(3)/3;

sin36° = sqrt[10-2sqrt(5)]/4; cos36° = [sqrt(5)+1]/4;

tan36° = {sqrt[50-10sqrt(5)]-sqrt[10-2sqrt(5)]}/4;

sin45° = sqrt(2)/2; cos45° = sqrt(2)/2;

tan45° = 1;

sin54° = [sqrt(5)+1]/4; cos54° = sqrt[10-2sqrt(5)]/4;

tan54° = {3sqrt[50-10sqrt(5)]+5sqrt[10-2sqrt(5)]}/20;

sin60° = sqrt(3)/2; cos60° = 1/2;

tan60° = sqrt(3);

sin72° = sqrt[10+2sqrt(5)]/4; cos72° = [sqrt(5)-1]/4;

tan72° = {sqrt[50+10sqrt(5)]+sqrt[10+2sqrt(5)]}/4;

sin75° = [sqrt(6)+sqrt(2)]/4; cos75° = [sqrt(6)-sqrt(2)]/4;

tan75° = 2+sqrt(3);

sin90° = 1; cos90° = 0;

tan90° = ∞;

2-1/,290.,260;3

sin45=根号2/,45,不算特殊角吧;cos15(自己算一下)

sin30=1/那些不用记的啊

只要记住30

45

60

就可以了

其他

考试时是不会考的

因为要用计算器来算

sin0=0

cos0=1

tan0=0

sin15=（根号6-根号2）/,305;2

tan15=sin15/2

1/2

根号3/,30,350这些是特殊角么，其他的都能通过诱导公式算出来

sin

cos

tan

0度

130度

1/2

cos30=根号3/2

-根号3/.;2

-根号3/2

-根号3

150度

1/.

这些要用到sin5和sin10;2

根号3/,335:其实只要熟记下0,60的就足够了;2

cos45=sin45

tan45=1

sin60=cos30

cos60=sin30

tan60=根号3

sin75=cos15

cos75=sin15

tan75=sin75/,230;2

根号3

90度

1不存在

120度

根号3/2

160度

根号3/2

cos15=（根号6+根号2）/3

45度

根号2/？

sin360=sin0

cos360=cos0

tan360=tan0

PS,245.,275;2

根号2/2

tan30=根号3/cos75（自己比一下)

sin90=cos0

cos90=sin0

tan90无意义

sin105=cos15

cos105=-sin15

tan105=-cot15

sin120=cos30

cos120=-sin30

tan120=-tan60

sin135=sin45

cos135=-cos45

tan135=-tan45

sin150=sin30

cos150=-cos30

tan150=-tan30

sin165=sin15

cos165=-cos15

tan165=-tan15

sin180=sin0

cos180=-sin0

tan180=tan0

sin195=-sin15

cos195=-cos195

tan195=tan15

215

那些不用记的啊 只要记住30 45 60 就可以了 其他 考试时是不会考的 因为要用计算器来算

sin0=0

cos0=1

tan0=0

sin15=（根号6-根号2）/2

cos15=（根号6+根号2）/2

tan15=sin15/cos15(自己算一下)

sin30=1/2

cos30=根号3/2

tan30=根号3/3

sin45=根号2/2

cos45=sin45

tan45=1

sin60=cos30

cos60=sin30

tan60=根号3

sin75=cos15

cos75=sin15

tan75=sin75/cos75（自己比一下)

sin90=cos0

cos90=sin0

tan90无意义

sin105=cos15

cos105=-sin15

tan105=-cot15

sin120=cos30

cos120=-sin30

tan120=-tan60

sin135=sin45

cos135=-cos45

tan135=-tan45

sin150=sin30

cos150=-cos30

tan150=-tan30

sin165=sin15

cos165=-cos15

tan165=-tan15

sin180=sin0

cos180=-sin0

tan180=tan0

sin195=-sin15

cos195=-cos195

tan195=tan15

215,230,245,260,275,290,305,335,350这些是特殊角么....

这些要用到sin5和sin10,不算特殊角吧？

sin360=sin0

cos360=cos0

tan360=tan0

PS:其实只要熟记下0,30,45,60的就足够了，其他的都能通过诱导公式算出来

sin cos tan

0度 0 1 0

30度 1/2 根号3/2 根号3/3

45度 根号2/2 根号2/2 1

60度 根号3/2 1/2 根号3

90度 1 0 不存在

120度 根号3/2 -1/2 -根号3

150度 1/2 -根号3/2 -根号3/3

180度 0 -1 0

270度 -1 0 不存在

360度 0 1 0

210,240,270,310,330,度的各角正弦,余弦函数值

sin210°=sin(180°+30°)=-sin30°=-1/2

sin240°=sin(180°+60°)=-sin60°=-√3/2

sin270°=sin(180°+90°)=-sin90°=-1

sin300°=sin(360°-60°)=-sin60°=-√3/2

sin330°=sin(360°-30°)=-sin30°=-1/2

cos210°=cos(180°+30°)=-cos30°=-√3/2

cos240°=cos(180°+60°)=-cos60°=-1/2

cos270°=cos(180°+90°)=-cos90°=0

cos300°=cos(360°-60°)=cos60°=1/2

cos330°=cos(360°-30°)=cos30°=√3/2

求下列三角函数为锐角三角函数 （1）cos210

cos210°=cos（180° +30°）=-cos30°+ =-（根号3）/2

Sin263°42′ = Sin(180°+ 83°42′)

= -sin83°42

cos(-π/6)

=cos(π/6)

=cos30°

=1/2

cos(－5π/3)=cos(5π/3)=cos(2π－π/3)=cos(π/3)=1/2

急！！！数学题？？

奇变偶不变，符号看象限

cos210°=cos（π+π/6）=-cosπ/6=-『3/2【不会打根号，『就代替根号了】

210°=π+π/6，π是π/2的偶数倍，

∴cos210°与cosπ/6数值相同，

∵210°在第三象限，∴cos210°是负值，∴cos210°=-cosπ/6

再如cos（-π/6）

-π/6在第四象限，∴cos（-π/6）是正值，即cos（-π/6）=cosπ/6=『3/2

记住奇变偶不变，符号看象限就行了

至于263度42分，我都忘了度与分的关系了

你自己看吧

用公式带啊 诱导公式啊

210度是第二象限的角 所以它的cos为负值 就等于-COS30度

263度42分化作度数是263.7度是第二象限角 所以它的sin为正 就等于sin83.7度

-6分之派相当于-30度 是第四象限角 它的cos为正就等于cos30度

cos210度=-cos30度=-√3/2

sin263度42分=-sin83度42分

COS(-∏/6)=cos(∏/6)=√3/2

熟悉诱导公式就可以了

cos210°=-cos（210-180）°=-cos30°