Question

If the equation ax2 + 2x + a = 0 has two distinct roots, if

A. a = ±1

B. a = 0

C. a = 0, 1

D. a = – 1, 0

Answer 1

If the roots of given equation are distinct then

d = b2 – 4ac = 0

⇒ d = b2 – 4ac = 0

⇒ 22 – 4(a) (a) = 0

⇒ 4 – 4a2 = 0

⇒ 4a2 = 4

⇒ a2 = 1

⇒ a = (\pm1)