Question

help on determining somthing

Answer 1

how do you know when you have a -complex solution- in a quadratic function?

Answer 2

when the inside of the "square root" is negative using the quadratic formula

Answer 3

or by graphing if it does not touch the x-axis

Answer 4

Quadratic equation \[\frac{-b \pm \sqrt{D}}{2a}\]
Where \[D = \sqrt{b^2-4ac}\]

Only when D becomes negative can it be imaginary because

\[\sqrt{-D}\] is imaginary.

Understood? :)

The graph usually looks like this.
It is a parabola which does not touch the x-axis and thus, does not have a real solution.

Answer 5

uhuh..... haha so in the quadratic equation you get the negative so the number in the square root can be imaginary therefore it will not touch the x-axis

Answer 6

Yes. bUT IF YOU REPRESENT IT ON THE ARGAND PLANE.
Where you can represent imaginary numbers, you can see them intersecting the x-axis! :D

Answer 7

I got it thank you!

Answer 8

:)