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 x2, the only posibilities would be ax2*b + cx*dx.
=x2*1 + x*8x + x*7x
=x2 + 8x2 + 7x2
=16x2
Therefore the coefficient of x2 is 16
+113 
