I'm studying for a test which will contain questions of how to obtain binomial coefficients, I understand the idea and can do it when the equation does not contain fractions but have trouble when it does contain fractions. How does one go from: (2x)^(9-k) (3/x)^k to... 2^(9-k) 3^k x^(9-2k) ??? I'm sure it's an easy year 8 level problem, But I have not worked with fractions for a long time and seem to have forgotten it! Thanks in advance! PS: For anyone actually interested in the binomial question, it is as follows: Find the coefficient of x in the expansion of (2x + 3/x)^9 I have the answer if anyone wants it, I just don't understand the fractions part which I asked about above.