What is the coefficient of x^2 in (x^3 + x^2 + x + 1)(x^4 + 3x^3 + 8x + 7x + 1)?
To find the coefficient of x^2 you have to multiply
(x^2)x1=x^2
and
(x)(8x+7x)=(x)(15x)=15x^2
you add x^2+15x^2 to get 16x^2 so the answer is 16
+349 
