Question

none

Answer 1

I just want to clarify something -- Do you want an example of a quadratic equation with discriminant -4? Or can it have any negative discriminant?

Answer 2

lol

Answer 3

I think I just need any negative discriminate, it doesn't have to be -4.

Answer 4

sandra such a n00b

Answer 5

Discriminant -4 example: \(x^2-2x+2 = 0\) (\(b^2-4ac = (-2)^2 - 4(1)(2) =-4\)).

(Other) Negative discriminant example: \(x^2+x+1 = 0\) (\(b^2-4ac = 1^2-4(1)(1) = -3\))

Answer 6

x^2=-4

Answer 7

As for the explanation, what you want to emphasize is that when the discriminant is negative, we can take the square root. However, the solution will no longer be real but instead complex (or imaginary, if you like that term better). The idea here is that we define \(i=\sqrt{-1}\) and thus \(\sqrt{-r} = i\sqrt{r}\), where \(r\) is any real number. You can still use the quadratic formula, but the solution is complex (imaginary) -- not real.

Answer 8

Thanks so much!

Answer 9

No problem! :-)