它们相等吗?咋证明?sin(x+∏/4)=cos(∏/4-x)?
证明sin^2(x)+cos^2(x+30)+sin(x)cos(x+30)=3/4
三角函数证明及化简题1.证明sin^6x+cos^6x=(sin^2x+cos^2x)(cos^4x-cos^2xsin
证明∫( 0,π/2 ) (f sin x/(f sin x+f cos x) dx=π /4
证明:sin(π/4-x)=cos(π/4+x)
求证明:sin的4次方x+cos的4次方x=1-2sin的2次方x乘cos的2次方x
根号下(sin""x+4cos"x)-根号下(cos""x+4sin"x)=?
化简下面的三角函数f(x)=sin^2x+2√3sin(x+∏/4)cos(x-∏/4)-cos^2-√3
设f(x)=(sin^4 x-cos^4 x-5)/(cos2x+2). (a)证明f(x)= 3/(2 sin^2 x
求证(cos^2 x-sin^2 x)(cos^4 x+sin^4 x)+1/4 sin 2x sin 4x=cos 2
两个个数学证明题1.证明:cos2x+sin2x=√2sin(sin2x+π/4)2.证明:αsinαx+cosαx=√
证明COS(X+Y)COS(X-Y)=COS^2X-SIN^2Y
sin^2x+cos^2x)(sin^4x-sin^2xcos^2x+cos^4x) =sin^4x-sin^2xcos