设Y=(1+X^2)arctanx,求(d^2y)/dx^2

Question

如题所述

Answer 1

7

Answer 2

用matlab中的diff进行求解，命令如下：
syms x;
>> y=(1+x^2)*atan(x);%y
>> dy=diff(y,x)；%dy/dx
>> d2y=diff(dy,x)；%d2y/dx2
>> pretty(d2y)%看结果