Question

Find the value of k so that the quadratic equation x² – 4kx + k = 0 has equal roots.

Answer 1

It is given that the quadratic equation x² – 4kx + k = 0 has equal roots. 

∴ D = 0 

⇒ (–4k)² – 4 × 1 × k = 0 

⇒ 16k² – 4k = 0 

⇒ 4k(4k – 1) = 0 

⇒ k = 0 or 4k – 1 = 0 

⇒ k = 0 or `k = 1/4`

Hence, 0 and `1/4` are the required values of k.