SimPug

In the expansion of (1 + x + x^2 + ...+ x^27) (1 + x + x^2 + ... + x^14) ^2 What is the coefficient of x^28? A) 195 B)196 C)224 D)378 Me and my sister are both trying to solve this for school, but keep getting stuck and are confused on it. If you could he...