- #1

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I know that i= the sq root of -1, and that i^2=-1, but I'm not sure how to approach this problem.

sq.rt.(-x^2-4x-3)

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- Thread starter TKDKicker89
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In summary, the problem is to simplify the expression \sqrt{-x^2-4x-3} and the approach is to complete the square by adding (4/2)^2 inside the parentheses. The result can be simplified to \sqrt{1-(x+2)^2} and further to \sqrt{(1-x)(3+x)} or \sqrt{(-1-x)(3+x)}.

- #1

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I know that i= the sq root of -1, and that i^2=-1, but I'm not sure how to approach this problem.

sq.rt.(-x^2-4x-3)

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- #2

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i would start by factoring out the -1 and seeing if i can't factor the polynomial more.

- #3

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TKDKicker89 said:

I know that i= the sq root of -1, and that i^2=-1, but I'm not sure how to approach this problem.

sq.rt.(-x^2-4x-3)

Exactly what

Any time you have something like this, involving a square root,even if it doesn't involve i, think about completing the square.

-x

-(x+2)

[tex]\sqrt{1-(x+2)^2}[/tex]. I don't see much more that can be done and I don't see that it has directly to do with i. Even though the original -x

- #4

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[tex]\sqrt{1-(x+2)^2}[/tex] can be simplified more

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- #6

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or even [tex]\sqrt{(-1-x)(3+x)}[/tex]

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