c) 2a^2 + 8b^2 – 8ab;
c) 2a2 + 8b2 – 8ab;
c) 2a2 + 8b2 – 8ab
= 2(a2 + 4b2 ‒ 4ab)
= 2[a2 ‒ 2.a.2b + (2b)2]
= 2(a ‒ 2b)2.