1.

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

Answer»

We know that quadratic equation ax2 + bx + c = 0 has equal roots if D = b2 – 4ac = 0. 

Therefore, given quadratic equation x2 – 4kx + k = 0 has equal roots if D = 0. 

⇒(−4k)2 – 4 × 1 × k = 0. (∵ In equation x2 – 4kx + k = 0, a = 1, b = – 4k & c = k) 

⇒ 16k2 – 4K = 0 

⇒ 4k (4k – 1) = 0

⇒ k = 0 or 4k – 1 = 0 

⇒ k = 0 or k = \(\frac{1}{4}\) .

Hence, for k = 1 and k = \(\frac{1}{4}\) , the quadric equation x2 – 4kx + x =0 has equal roots.



Discussion

No Comment Found

Related InterviewSolutions