Question

Write the set of value of k for which the quadratic equations has 2x² + kx − 8 = 0 has real roots.

Answer 1

The given quadric equation is, and roots are real.

Then find the value of k.

Here,

As we know that

Putting the value of

The given equation will have real roots, if

I.e.,

Therefore, for all real values of k, the given equation has real roots.