Integral, an algebra problem actually

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    Algebra Integral
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Homework Help Overview

The discussion revolves around evaluating the integral \(\frac{4}{3}\int_{0}^{1} x^8 \sqrt{1 + 4x^2 + 4x^4}dx\), which involves algebraic manipulation and potential substitutions. The subject area includes integral calculus and algebraic expressions.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster considers using a trigonometric substitution but is uncertain about how to simplify the expression under the square root. Another participant points out that the expression forms a perfect square, which prompts further reflection.

Discussion Status

Participants are actively engaging with the problem, with one suggesting a simplification that reveals a perfect square. There is a cautionary note about the implications of the square root, indicating that multiple solutions may exist.

Contextual Notes

One participant mentions previous experience with similar problems, noting discrepancies in answer choices due to the consideration of negative solutions from the square root, highlighting the importance of careful interpretation.

mattmns
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This one has me baffled.

[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.
 
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The stuff under the square root forms a perfect square.

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

Thanks!
 
i did this type of problem before but a multiple choice questions, and there is no matched answer.

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

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