- #1

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[tex]\frac{4}{3}\int_{0}^{1} x^8 \sqrt{1 + 4x^2 + 4x^4}dx[/tex]

Any ideas would be great, I am thinking maybe a trig substitution, but I have yet to figure out how to simplify this thing first. Thanks.

- Thread starter mattmns
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- #1

- 1,085

- 6

[tex]\frac{4}{3}\int_{0}^{1} x^8 \sqrt{1 + 4x^2 + 4x^4}dx[/tex]

Any ideas would be great, I am thinking maybe a trig substitution, but I have yet to figure out how to simplify this thing first. Thanks.

- #2

George Jones

Staff Emeritus

Science Advisor

Gold Member

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The stuff under the square root forms a perfect square.

Regards,

George

Regards,

George

- #3

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Pff, duhhh! [tex] (x^2 + \frac{1}{2})^2 [/tex]

Thanks!

Thanks!

- #4

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later i discovered they used the negative solution, since square root gives positive and negative. so be careful.

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