Deciding zero's to a polynomial function

Hi, the question I have to answer is the following: "Decide all the zeros to the function : 0.1x^3 - 5x^2 –x +e^-x = -4, x>0"

I want to know how I can represent this function in matlab? I can't seem to input exp/e. Thanks.

Any help on finding the roots would also be appreciated. Thanks in advance!

Answer 1

[Roger Stafford]

Use 'fzero' and replace e^-x with exp(-x).

[Brian]

I'm confused about what to enter, I had this but I'm clearly doing something wrong.

y=[0.1*x.^3 +5*x.^2 -1*x exp(-x)]

fzero(y)

thanks

[Brian]

I still can't get fzero to work :/ thanks for your help so far