计算:cos(70°+α)sin(170°-α)-sin(70°+α)cos(10°+α)
来源:学生作业帮助网 编辑:作业帮 时间:2024/05/13 16:20:00
计算:cos(70°+α)sin(170°-α)-sin(70°+α)cos(10°+α)
计算:cos(70°+α)sin(170°-α)-sin(70°+α)cos(10°+α)
计算:cos(70°+α)sin(170°-α)-sin(70°+α)cos(10°+α)
sin x = sin (180° - x)
所以,
sin (170° - a) = sin [180° - (170° - a)]
= sin (10° + a)
根据方程式,
sin(u ±v) = sin u cos v ± cos u sin v
sin (10° + a) cos (70° + a) - cos (10° + a) sin (70° + a)
= sin [(10° + a) - (70° + a)]
= sin - 60°
= - sin 60°
= -(√3)/2
= -0.866
纯手打,蒙采纳,谢谢~~
计算:cos(70°+α)sin(170°-α)-sin(70°+α)cos(10°+α)
cos(70+a)cos( 10+a)+sin(70+a)sin(170-a)计算
计算:sin^67.5°-cos^67.5度
计算 cos(40° +A)*sin(10°+A)+sin(40°+A)*cos(170°-A)
sin(70° a)cos(10° a)-cos(70° a)sin(170°-a)
设tanα=2,计算sinα+cosα/sinα-cosα
设tanα=2,计算sinα+cosα/sinα-cosα急
根号3cosα-sinα/根号3cosα+sinα计算
[cos(α+β)-cos(α-β)]/[sin(α+β)-sin(α-β)]要有计算过程
电脑怎么计算cos,sin
已知tanα=3,计算sinαcosα
已知tanα=3,计算:sinαcosα
计算tanα+cosα/(1+sinα)
已知tanα=1/3,计算(1)sinα+2cosα/5cosα-sinα,(2)1/2sinαcosα+cos^α
已知tanα=1/3 .计算 sinα+2cosα/5cosα-sinα ,1/2sinαcosα+cos平方α
已知tanα=3计算(sinα+cosα)² sinαcosα 1/2sinαcosα+cos²α
计算:sin(-1665°)+cos(-330°)-tan1200°
化简:(2)cos(70°+α)sin(170°+α)-sin(70°+α)cos(10°+α)