Correct Answer: a2 b2
Explanation:
a2 b4 + 2 a2 b2 = a2 b2 ( b2 +2).......................(i) and (ab)7 - 4 a2 b9 = a7 b7 - 4 a2 b9 = a2 b2(a5 b5 - 4b7)................(ii)from Eqs. (i) and (ii) HCF = a2 b2