Consider the function:

f(x) = x^2* e^(-x)

.

I want to find the point that makes the derivative of this function zero. My code is:

`syms xf=(x.^2).*exp(-x);k=diff(f);a = @(x) k;b=fzero(a,0,1000)`

I am getting this error:

"Function value at starting guess must be finite and real."

What do you think it is wrong?

## Best Answer