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Homework Help: How do I solve this integrals?(dy/secˆ2(y))(dx/(-xˆ2 + x))

  1. Feb 13, 2006 #1
    How do I solve this integrals?

    (dy/secˆ2(y))

    (dx/(-xˆ2 + x))
     
  2. jcsd
  3. Feb 13, 2006 #2
    Partial integration or use the formula's linking cos(x) to cos(2x)

    Partial fractions .

    marlon
     
    Last edited: Feb 13, 2006
  4. Feb 13, 2006 #3

    VietDao29

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    Homework Helper

    #1, [tex]\int \frac{dy}{\sec ^ 2 y} = \int \frac{dy}{\frac{1}{\cos ^ 2 y}} = \int \cos ^ 2 y dy[/tex]
    Now, do you know the Double-angle formulae?
    #2, I'll give you a hint, try to complete the square in the denominator, then use u-substitution, and it's done:
    [tex]\int \frac{dx}{-x ^ 2 + x} = - \int \frac{dx}{x ^ 2 - x}[/tex]
    Can you go from here? :)
     
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