Question

Find the value(s) of  'k' so that the quadratic equation 4x² + kx + 1 = 0 has real and equal roots.

Answer 1

For a quadration equation ax² + bx + c = 0 to have red and equal roots, the discriminant must be zero.

d = b² − 4ac = 0

Here, a = 4, b = k, c = 1

k² − 4 (4) (1) = 0

k² − 16 = 0

k = ± 4

∴ k = 4 or k = −4