Question

Let a, b be non-zero real numbers. Which of the following statements about the quadratic equation ax² + (a+b)x + b = 0 is necessarily true?

I. It has at least one negative root.

II. It has at least one positive root.

III. Both its roots are real.

(a) I and II only

(b) I and III only

(c) II and III only

(d) All of them

Answer 1

Answer is : (b) I and III only

We have,

It has at least one negative root, i.e. −1. So, it has both roots are real.

∴ Option (b) is correct.