(6cos^4x-sin^2x-1)/(2(2cos^2x -1))怎么化简

2cos x (sin x -cos x)+1 lim(sin(x^2*cos(1/x)))/x怎么做? 化简[1-(sin^4x-sin^2cos^2x+cos^4x)/(sin^2)]+3sin^2x 求证（cos^2 x-sin^2 x)(cos^4 x+sin^4 x)+1/4 sin 2x sin 4x=cos 2 Sin^x怎么变化成 1-cos(2x) /2 cos^2 x - sin^2 x 是怎么化简=cos 2x (sin^2x+cos^2x )(sin^2x-cos^2x)怎么得sin^2x-cos^2x? 化简 1/2cos x-根号3/2sin x 根3sin x+cos x 化简（1)√3sin x+cos x (2）√2(sin x-cos x) （3）√2cos x-√6sin x ∫[1/(sin^2(x)cos^4(x)]dx 函数f(x)=-√2(sin2x+π/4)+6 sin x cos x-2cos²x+1 MATLAB画图,y=sin(x)*(cos(x)-1)/((2*sin(x.^2)+4*cos(x)).^0.5)-(