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Math Help - Definite Intergral Post

  1. #1
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    Definite Intergral Post

    I'm a little stumped the equation is x sqrt (1-x^4) using substitution. Thanks sososososo much in advance.
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  2. #2
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    x^2=sin(y) is a good substitution
    dx=1/2 cos(y)/sin^.5(y) dy
    sqrt(1-x^4)=cos(y)

    you will be integrating 1/2 cos^2(y) dy
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  3. #3
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    Quote Originally Posted by samer_guirguis_2000 View Post
    x^2=sin(y) is a good substitution
    dx=1/2 cos(y)/sin^.5(y) dy Mr F remarks: {\color{red}dx = \frac{1}{2} \frac{\cos y}{x}} is sufficient - there's no need to express x in terms of y.

    sqrt(1-x^4)=cos(y)

    you will be integrating 1/2 cos^2(y) dy
    ..
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