# Math Help - Multinomial Expansion

1. ## Multinomial Expansion

Find number of dissimilar terms in the expansion $(1+ax^p+bx^q+cx^r)^n$ where p,q,r are different integers and n is a non-negative integers.(p,q,r may be either positive or negative and a,b,c are any real numbers)
Does there exist a general formula?

3. i am famaliar with this formula.but does it work in this case.For e.g. in expansion of $(1-3x+7x^2)^n$ there are $2n+1$ dissimilar terms.