cos(ax)的导数-搜答案-搜狗做题网

求cos^3 (3x)的导数?

{cos^3(3x)}'=3cos^2(3X){cos(3x)}'=3cos^2(3X){-sin(3x)}(3x)'=3cos^2(3X){-sin(3x)}3=-9sin(3x)cos^2(3x)

y'=(sinx)'+(cos^5x)'=cosx-5cos^4x*sinx符合函数的求导,其实就是对式子一层一层的求导.对于cos^5x,可以看做a=cosx,b=a^5.再一层层求导就可以了

这是复合函数,f(x)=x^2g(x)=cosxh(x)=lnx所以f{g[h(x)]}=[cos(Inx)]^2所以首先对平方求导,再对cos求导,最后对ln求导所以f'(x)=2cos(lnx)*

12cos(3x)cos(x)-4sin(3x)sin(x)

求COS²X的N阶导数

方是哪个的方?xcos(x^2)的导数=cos(x^2)-2(x^2)sin(x^2)x*(cosx)^2=(cosx)^2+xsin(2x)(xcosx)^2=2(xcosx)(cosx-xsinx

y'=[-sinx(1-sinx)-cosx(-cosx)/(1-sinx)²=[-sinx+sin²x+cos²x]/(1-sinx)²=1/(1-sinx)

y=sin^nxcos^nxy′=nsin^(n-1)xcosxcos^nx+ncos^(n-1)x(-sinx)sin^nx=nsin^(n-1)xcos^(n-1)x(cos²x-sin

计算结果：nCos[x]Cos[nx]Sin[x]^(-1+n)-nSin[x]^nSin[nx]

y'=-sin[ln(1+2x)]×[ln(1+2x)]'=-sin[ln(1+2x)]×1/(1+2x)×(1+2x)'=-sin[ln(1+2x)]×1/(1+2x)×2=-2sin[ln(1+2

[cos(1+x)]=-sin(1+x)*(1+x)'=-sin(1+x)再问：如果是求cos(1+x^2)的导数？再答：属于复合函数。y=cos(1+x)可以设t=x+1，则dy/dt=-sint,

求cos(x^2)的导数

-2xsin(x^2)

(cos(3x))'=-sin(3x)*(3x)'=-3sin(3x)

cos(3-x)'=-sin(3-x)*(-1)=sin(3-x)

对x求导-sinxy*(xy)'=1(xy)'=x'*y+x*y'=y+x*y'所以y+x*y'=-1/sin(xy)y'=-[1/sin(xy)+y]/x

cos(nx)的导数为?

d[cos(nx)]=-sin(nx)d(nx)=-nsin(nx)dxd[cos(nx)]/dx=-nsin(nx)

复合函数求导y'=[cos（sinx）]'=sin(sinx)·（sinx）‘=sin（sinx）·cosx

ln(cos 8θ）的导数

对θ求导是1/cos8θ*（-sin8θ）*8=-8tan8θ解毕~望采纳~一楼不对.楼主注意了

(x*sinx*cosx)'=(1/2xsin2x)'=1/2(sin2x+xcos2x*2)=1/2sin2x+xcos2x

y'=2cos(sin2x)×[cos(sin2x)]'=2cos(sin2x)×[-sin(sin2x)]×(sin2x)'=-sin(2sin2x)×2cos2x=-2cos2xsin(2sin2