y=f(x³ cos2x)则dy dx=-搜答案-搜搜考试网

设y=f(-x^2) 则dy=

--2xdx,负2xdx再问：过程呢再答：这是个非常简单的微分运算，如果你是自学高等数学你可以上网搜‘’‘’‘’微分；；；；过程就是根据求导法则，

根据复合函数求导法则dy/dx=[f(x^2)]'=f'(x^2)*(x^2)'=2xf'(x)

两边对x求导有y'e^y=y+xy'整理解得y‘=dy/dx=x/(e^y-x)

y=f[(x-1)/(x+1)],f'(x)=arctanx^2,求dy/dx,dy两边对x求导：dy/dx=f'[(x-1)/(x+1)]*2/（x+1)^2=arctan[(x-1)/(x+1)]

2e^tan2x*(1/(1+4x^2))-2sin2x*e^cos2x2x*e^x^2对2x+1求积分,得曲线方程为x^2+x+C,又曲线经过（0,1）代入曲线方程得C=1,所以曲线方程为：x^2+

dy/dx=y'=e^x(cos2x+sinx)+e^x(cos2x+sinx)'=e^x(cos2x+sinx-2sin2x+cosx)

y=sinx/(1-cos2x).=sinx/(2sin^2x)=(1/2)(1/sinx).=(1/2)cscx.∴dy/dx=-cscx*cotx.

d(e^x+e^y)=dyde^x+de^y=dye^xdx+e^ydy=dy(1-e^y)dy=e^xdxdy/dx=e^x/(1-e^y)

做任务的.

dy=d[cos2x/(x-1)]=y'dx={[-2sin2x*(x-1)-cos2x]/(x-1)^2}dx=-[2sin2x*(x-1)+cos2x]/(x-1)^2dx

y'=f'(sin^2x)*(sin^2x)'=g(sin^2x)*2sinxcosx

函数f(x)可导,设其导函数为g（x）dy/dx=df(x^2)/dx=g（x^2)*dx^2/dx=2x*g(x^2)

y=f(x-y)dy/dx=f'(x-y)*d(x-y)=f'(x-y)*(1-dy/dx)=f'(x-y)-f'(x-y)*dy/dx[1+f'(x-y)]dy/dx=f'(x-y)dy/dx=f'

复合函数求导公式：d(u(v))/dx=u'(v)*v'dy/dx=f'(sin2x)*(sin2x)'+f'(cos2x)*(cos2x)'=f'(sin2x)*cos2x*(2x)'+f'(cos

f(cosx)=cos2x 则f(x)=

令T=cosx,f（T）=2T^2-1所以f（x）=2x^2-1,x∈【-1,1】

两边求微分：d(x^y+y^x)=d(f(x^2+y^2))对x^y可以这么看：先把X看成常数,对Y求微分相当于a^Y,再把Y看成常数对X求微分相当于X^a.那么就好用公式了如下：d(x^y）=X^Y

sinx的导数是cosxcosx的导数是-sinx结合求导的知识可知原式=2cos2x+2sin2x

-f'(e^-x)e^-x再问：是负数吗再答：是的

积分区域为：y=xy=0及x=a所围部分.故选C