sin(x-π/4 + π/2 )=-cos(x+

sin(x-π/4 + π/2 )=-cos(x+π/4)

1个回答

求证:sin(π/4+x)/sin(π/4-x)+cos(π/4+x)/(π/4-x)=2/cos2x
已知函数f(x)=cos(x+π/4)cos(x-π/4)+2tsinxcosx-sin(x+π/4)cos(x-π/4
f(x)=2cos(x+π/4)cos(x-π/4) =sin(2x-π/2) 其中cos(x-π/4) 是如何变成si
f(x)=1-2sin^2(x+π/8)+2sin(x+π/8)*cos(x+π/8)=cos(2x+π/4)+sin(
化简sin(3π-x)cos(x-3/2)cos(4π-x)/tan(x-5π)cos(π/2+x)sin(x-5/2π
y=sin(π/4+x/2)sin(π/4-x/2) =sin(π/4+x/2)sin[π/2-(π/4+x/2)]
化简cos2x/【sin（x+π/4）sin（x-π/4）】=?
求y=sin(x-π/4)cos(x+π/4）的反函数（1）x属于【-π/4,π/4】（2）x属于【π/4,π/2】
为什么 cos（x/2-π/4）=sin（π/4+x/2）
已知函数fx=cos(2x-π/3)+2sin(x-π/4)sin(x+π/4)