1- sin(2π/3 - a)/sina
1- sin(2π/3 - a)/sina
f(x)=(2cos^2 a/2-sina-1)/(sin(a+π/3)sin(a-π/3)
已知tan{π/4+a}=3,求sina*sin(3π /2 +a)-sin^2a+1的值
已知sin(π+a)=1/3,则sina=
sin(3π-a)=sina?
若sinA+cosA/sinA-cosA=2,则sin(A-5π)*sin(3π/2-A)等于?
在△ABC,sinA+cosA=1/3,-cos(3π-A)-sin(A-π)/sin(π/2+A)+sin(-A)的值
证明sinA+sin(A+2π/3)+sin(A-2π/3)=0
sina(cosa)^3=1/4sin 2a+1/8sin 4a证明过程
已知sin(A+π/4)+sin(A-π/4)=根号2/3 1.求sinA的值 2.求【sin(A-π/4)】/【1-c
sin(a-2π)*sin(π+a)为什么等于sina(-sina)啊……
(2sin^2a+sin2a)/(1+tana) 整理 =[2sina(sina+cosa)]/[(sina+cosa)