Question

If one root of 5x² + 13x + k = 0 be the reciprocal of the other root then the value of k is ______.

Options

• 0

• 1

• 2

• 5

Answer 1

If one root of 5x² + 13x + k = 0 be the reciprocal of the other root then the value of k is 5.

Explanation:

Let the roots of the equation `-2/3` be a and `1/a`. 

∴ Product of the roots = `c/a`

⇒ `a xx 1/a = k/5` 

⇒ `a = k/5` 

⇒ k = 5