(За - а^2)^2 - а^2 (а - 2)(а + 2) + 2а (7 + 3а^2)

Question

(За - а^2)^2 - а^2 (а - 2)(а + 2) + 2а (7 + 3а^2)

Answer 1

(3a-aˇ2)ˇ2 -aˇ2(a-2)(a+2)+2a(7+3aˇ2)=
=9aˇ2-6aˇ3+aˇ4-aˇ2(aˇ2-4)+14a+6aˇ3=
=9aˇ2-6aˇ3+aˇ4-aˇ4+4aˇ2+14a+6aˇ3=
=13aˇ2+14a