How to set assumptions in matlab

[sara_87]

Homework Statement

I want to know how to set assumptions in Matlab. i want to integrate 3*a*x/b but i want to tell MATLAB that b is less than a.

Homework Equations

The Attempt at a Solution

I know how to set assumptions that a variable is real/nonreal/positive/negative.
eg: sym('a','positive')
but not specific assumptions as b<a.

Thank you in advance.

 

[viscousflow]

Can you use another program? Wolfram Alpha is good with these things. http://www.wolframalpha.com/