Find the values of m which make the following quadratic function a perfect square. x2 + 2(m + 1)x + m + 3

A.

-1, 1

B.

-1, 2

C.

1, -2

D.

2, -2

Correct answer is C

x2 + 2(m + 1)x + m + 3 from (A + B)2 = a2 + 2AB + b2

2B = \(\frac{2(m + 1)}{2}\) = m + 1 .......(i)

Also B2 = m + 3..........(ii)

Subst. for B in equation ..........(iii)

= (m + 1)2 = m + 3 = m2 + 2m + 1 = m + 3

= m2 + 2m - m + 1 - 3 = 0

m2 + m - 2 = 0

(m + 2)(m - 1) = 0 or m - 1 = 0

m = -2 or 1