Question

Choose the correct answer from the given four options :

If `(1)/(2)` is a root of the quadratic equation 4x² – 4kx + k + 5 = 0, then the value of k is

Options

• – 6

• – 3

• 3

• 6

Answer 1

`(1)/(2)` is a root of the equation
4x² – 4kx + k + 5 = 0

Substituting the value of x = `(1)/(2)` in the equation

`4(1/2)^2 - 4 xx k xx (1)/(2) + k + 5` = 0

1 – 2k + k + 5 = 0
⇒ – k + 6 = 0
k = 6.