How can I math formula to matla code using double integration

Hi, I want use double integration such as int(int) {A-B}f(x)dx*q(r)dr

What I want to know is how can I make code from "f(x)dxq(r)dr"

[Walter Roberson]

I showed one possibility in http://www.mathworks.co.uk/matlabcentral/answers/76511-how-can-i-make-double-integration