Originally Posted by

**Ifailatmaths** C1 exam tormorrow, got some last minute questions.

5.The equation $\displaystyle 2x^2 -3x - (k + 1) = 0$, where k is a constant, has no real roots.

Find the set of possible values of k.

So I use $\displaystyle b2-4ac<0$?

If the question said:

5.The equation $\displaystyle 2x^2 -3x - (k + 1) = 0$, where k is a constant, has equal roots.

I would use: $\displaystyle \sqrt b2-4ac=0$?

And if the question said

5.The equation $\displaystyle 2x^2 -3x - (k + 1) = 0$, where k is a constant, 2 real roots.

I would use: $\displaystyle b2-4ac>0$?