(sina/2+cosa/2)^2+2sin^2(π/4-a/2)=
(2sin^2a+sin2a)/(1+tana) 整理 =[2sina(sina+cosa)]/[(sina+cosa)
若sinA+cosA/sinA-cosA=2,则sin(A-5π)*sin(3π/2-A)等于?
已知tana=3,求①sina+cosa/2sina-cosa ②sin²a+sina·cosa+3cos
cos^2a-sin^2a=(cosa+sina)(cosa-sina)吗?
sina+cosa/sina-cosa=2 求sin^2a-2sinacosa+1
Sin^4a+Sina*Cosa+Cos^2a化简
已知sin a+cos a=1/2 sina*cosa=?cos a/sina+sina/cosa=?
已知sin(pai-a)-2cosa=0若sina
若(sina+cosa)/(sina-cosa)=2,则sin(a-5pai)*sin(3pai/2-a)等于?
若(sina+cosa)/(sina-cosa)=2,则sin(a-5派)*sin(3派/2-a)等于?
sina(cosa)^3=1/4sin 2a+1/8sin 4a证明过程
1:已知sina+cosa=根2求sina cosa sin(4方)a+cos(4方)的值