This is giving me some trouble and I need an answer soon.

The equation is: x^2 - 6x + 38

And there are 2 answers, which I assume is b + something, and b - something.

I just don't get it. (Angry)

Thanks in advance.

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- Jun 17th 2008, 09:43 PMmankvillpolynomial equations!
This is giving me some trouble and I need an answer soon.

The equation is: x^2 - 6x + 38

And there are 2 answers, which I assume is b + something, and b - something.

I just don't get it. (Angry)

Thanks in advance. - Jun 17th 2008, 09:55 PMReckoner
This is not an equation, it is an expression. Did you mean $\displaystyle x^2 - 6x + 38 = 0$?

If that's the case, then this equation has no solutions over the reals since the discriminant, $\displaystyle b^2 - 4ac = 6^2 - 4\cdot1\cdot38 = -116$, is negative. If you want to find the complex solutions, use the quadratic formula:

$\displaystyle x = \frac{-b\pm\sqrt{b^2 - 4ac}}{2a} = \frac{6\pm\sqrt{36-152}}{2}$

$\displaystyle = 3\pm\frac{\sqrt{-116}}2 = 3\pm\frac{i\sqrt{116}}2 = 3\pm\frac{2\sqrt{29}}2\,i$

$\displaystyle \boxed{= 3\pm\sqrt{29}\,i}$ - Jun 17th 2008, 09:56 PMmankvill
That is what I meant, thank you very much!