Question

(d^2+6d+9)+(d^3+6d+9)

Answer 1

= d^3 + d^2 + 12d + 18

Explanation:

(d^2 + 6d + 9) + (d^3 + 6d + 9)

= d^2 + 6d + 9 + d^3 + 6d + 9

= d^3 + d^2 + 6d + 6d + 9 + 9

= d^3 + d^2 + 12d + 18