MATlab wont do integrate command

Matlab only gives errors when the script is:

int(x)
%or
int(x,x)
%or
int(x+5,x)

I just want to get answers such as .5x^2, or .5x^2+5x.

The error is: Undefined function 'int' for input arguments of type 'double'.

I have Symbolic Math Toolbox Version8.2 (R2018b) running

Answer 1

[Asad Mirza]

You have to first initialize x as a symbolic variable. You can find more information and examples here.

syms x 
f = .5*x^2
int(f)