∫ [cos^3(x)]/[sin^2 (x)]dx

已知sin(x)+3cos(x)=2,求sin(x)-cos(x)/sin(x)+cos(x)=? ∫(cos^3x/sin^2x)dx ∫ [cos^3(x)]/[sin^2 (x)]dx ∫sin^3(x)cos^2(x)dx= 求积分：∫sin^2 (x) /cos^3 (x) dx ∫sin(x) cos^2(x)dx sin[cos^2(x^3+x)],求导 2sin^2x - 5sin x cos x=3 cos^2x,求X, 化简[1-(sin^4x-sin^2cos^2x+cos^4x)/(sin^2)]+3sin^2x 化简 1/2cos x-根号3/2sin x 根3sin x+cos x 化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x) 证明sin^2(x)+cos^2(x+30)+sin(x)cos(x+30)=3/4 sin^3 x -cos^3 x sin^3 x -cos^3 x =(sin x -cos x )(sin^2 x +sin x*cos x +cos^2 x )问下这个是个公式还是什么?怎么样算出来的? ∫ {cos(x/2)[cos(x/2+sin(x/2)]} dxcos*sin有公式么? 2(sin^6x+cos^6)-3(sin^4x+cos^4x) (sin x*sin 3x)sin^2 x+（cos x*cos 3x)cos^2 x 如何变到1/2[(cos 2x-cos4x)sin^2x+(cos2x+cos4x)cos^2x] Sin x-sin y=2/3 cos x-cos y=1/2 求cos(x-y) (1-(sin^4x-sin^2xcos^2x+cos^4x)/sin^2x +3sin^2x