The term that should be added to (4x2 + 8x) so that resulting expression be a perfect square is:
Answer: (1) 4
4X2 + 8 X + 4 = (2X + 2)2 [(a + b)2 = a2 + b2 + 2 ab]
(2X + 2)2 is a perfect square.
Thus, the answer is (1) 4.