Question

If the zeroes of the quadratic polynomial ax² + x + a are equal, then a = ______.

Answer 1

If the zeroes of the quadratic polynomial ax² + x + a are equal, then a = `underlinebb(±1/2)`.

Explanation:

For equal roots the discriminant must be zero.

Here Δ = 1² – 4 × a × a

= 1 – 4a² 

= 0

So 4a² = 1

⇒ `a^2 = 1/4` 

⇒ `a = ±1/2`