x^ 3(sin x )^2/x^ 4+2x +1在[-1,1]的定积分

傅里叶级数作图f（x）=2sin[x] - sin[2x] + 2/3sin[3x] - 1/2sin[4x]我用mathematica输入程序Plot[{2sin[x],-2sin[x],2sin[x] - sin[2x],-2sin[x] + sin[2x],2sin[x] - sin[2x] + 2/3sin[3x],-2sin[x] + sin[2x] - 2/3sin[3x],2sin[x] - sin[2x] + 2/3si (1-(sin^4x-sin^2xcos^2x+cos^4x)/sin^2x +3sin^2x 化简[1-(sin^4 x-sin^2 xcos^2 x+cos^4 x)]/(sin^2 x)+3sin^2 x 化简[1-(sin^4x-sin^2cos^2x+cos^4x)/(sin^2)]+3sin^2x 求导f(x) = 4x^3 + sin(x^2) 证明sin^2(x)+cos^2(x+30)+sin(x)cos(x+30)=3/4 化简sin^4x-sin^2x+cos^2x 化简:sin^4 x-sin^2 x+cos^2 x s = 2*sin(x)-sin(2*x)+2/3*sin(3*x)-1/2*sin(4*x)+2/5*sin(5*x)用matlab画图,求教啊 三角等式求证：cos^6x+sin^6x=1-3sin^2x+3sin^4x lim (x->0) sin(3x)+4x/xsec(x) 求证(3-sin^4 x-cos^4 x)/2cos^2 x=1+tan^2 x+sin^2 x 2(sin^6x+cos^6)-3(sin^4x+cos^4x) 化简2sin^2[(π/4)+x]+根号3（sin^x-cos^x）-1 f(x)=cos(2x-x/3)+2sin(x-π/4)sin(x+π/4)sin(x+π/4)化简. 已知sin(x)+3cos(x)=2,求sin(x)-cos(x)/sin(x)+cos(x)=? 2sin^2x - 5sin x cos x=3 cos^2x,求X, 化简sin^4x+cos^2x