求证:sin(π/4+x)/sin(π/4-x)+cos(π/4+x)/(π/4-x)=2/cos2xsin(π/4+x)/sin(π/4-x)+cos(π/4+x)/cos(π/4-x)=2/cos2x

求证:(sin 2x /(1-cos 2x) )·(sin x /(1+sin x))=tan (π/4-x/2). sin(x+π/4) 求证sinx-cosx=根号2sin(x-π/4) 2sin(x+π/4)sin(x-π/4)=? sin(x+π/4)sin(x-π/4)等于什么? sin^2(π/4 +x) y=1+sinπX是周期函数吗?求证 求证:sin(π/4+x)/sin(π/4-x)+cos(π/4+x)/(π/4-x)=2/cos2xsin(π/4+x)/sin(π/4-x)+cos(π/4+x)/cos(π/4-x)=2/cos2x 求证 sin(x+π/3)-√3cos(2π/3-x)+2sin(x-π/3)=0 已知x+y=根号2sin(a+π/4),x-y=根号2sin(a-π/4),求证x^2+y^2=1 已知x+y=根号2sin(a+π/4),x-y=根号2sin(a-π/4),求证x^2+y^2=1 已知x+y=根号2sin(α+π/4),x-y=根号2sin(α-π/4),求证x²+y²=1 求证：2sin(π/4+a)sin(π/4-a)=cos2a f(x)=（1+cotx)sin^2x-2sin(x+π/4)sin(x-π/4)还有一题, 已知函数f(x)=(1+1 anx)sin^2x+m sin(x+π/4)sin(x-π/4) 三角等式求证：cos^6x+sin^6x=1-3sin^2x+3sin^4x 求证sin^4x-cos^4x=sin^2x-cos^2x 求证sin²x-sin²y=sin(x+y)sin(x-y)