Question

(x^7+x^6)(x^7+x^6-x^5)
multiply

Answer 1

x^6* ( x + 1 ) * x^5 * ( x² + x + 1)
= x^11 * ( x + 1) * ( x ² + x + 1 ) = x^11 * (x³ + x² + x + x² + x + 1) =
x^11 * ( x³ + 2x² + 2x + 1 ) = x^14 + 2x^13 + 2x^12 + x^11

Answer 2

just to confirm, x^14+2 x^13-x^11