Correct option is D
Given:
ab = 7
Concep used:
Using the identity for and
Solution:
we calculate a + b and a - b:
= 50 +2 7 = 50+14 = 64
= 50- 27 = 50-14 = 36
So,
a+b = = 8 (take positive root as a +b > 0)
a−b = = 6 (take positive root as a>b)
Now, we can find
=
Thus, correct option is (d)