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phoenirius
Dec 29, 2005, 03:52 PM
I have to solve 4x^2 -2x=-1 for its complex roots, this is what I have so far
4x^2-2x=-1
4x^2-2x-1=0
a=4, b=(-2), c=(-1)

x=-b +- sqrt b^2-4ac / 2a
=-4 +- sqrt (-2)^2-4(4)(-1) / 2(4)
=-4 +- sqrt (-4) +16 / 8
=-4 +-sqrt12/8
=-4+- sqrt3 * sqrt4/8

Now I'm stuck, it seems like I did something wrong because I don't know how to finish it off. Can anybody help me.
Thank you.

CaptainForest
Dec 29, 2005, 08:08 PM
You wrote:
4x^2-2x=-1
4x^2-2x-1=0
a=4, b=(-2), c=(-1)

You should have wrote:
4x^2-2x=-1
4x^2-2x+1=0
a=4, b=(-2), c=(1)

It is not -1=0, it is +1=0