cos^2x-sin^2x等于多少?
sin^2(x)cos^2(x)积分等于多少
cos^2x-sin^2x等于多少?
sin(sin(sin(sin(x)=cos(cos(cos(cos(x),X等于多少?
sin(-x) cos(-x)等于多少
sin^2(x/2)]*[cos^2(x/2)]等于多少啊
SIN(30度-X)=1\3,则COS(120度+2X)等于多少.
f(x)=cos^3x+sin^2-cosx上的最大值等于多少?
[sin^2(x)-cos^2(x)] 为什么等于-cos2x
证明sin x+cos x的最大值等于 根号2
sin^3x-cos^3x化简等于多少
cos^4(x)-sin^4(x)等于?是cos^2(x)还是cos2x
sin x(sin x+cos x)=1求x等于多少