Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Integral Substituion Rule

  1. Jul 15, 2008 #1
    1. The problem statement, all variables and given/known data

    as 0 goes to a [tex] \int \sqrt x_{a^2-x^2} \ {dx} [/tex]

    2. Relevant equations

    Substitution Rule

    3. The attempt at a solution

    I need help starting it, i dont understand at all
     
    Last edited: Jul 15, 2008
  2. jcsd
  3. Jul 15, 2008 #2

    Dick

    User Avatar
    Science Advisor
    Homework Helper

    You could try a trig substitution. Does anything come to mind?
     
  4. Jul 15, 2008 #3
    sorry how do i put an x before the square root
    its supposed to be there
     
  5. Jul 15, 2008 #4

    Dick

    User Avatar
    Science Advisor
    Homework Helper

    If you get into tex problems then just say it in words, i.e. integral from 0 to a of x*sqrt(a^2-x^2)dx. Is that what you mean? In that case try the even simpler substitution of u=a^2-x^2.
     
  6. Jul 16, 2008 #5

    Dick

    User Avatar
    Science Advisor
    Homework Helper

    Is this it?
    [tex]
    \int_0^a x \sqrt{a^2-x^2} \ {dx}
    [/tex]
     
  7. Jul 16, 2008 #6
    yeah thanks
     
  8. Jul 16, 2008 #7

    HallsofIvy

    User Avatar
    Science Advisor

    With that x dx, there is a very simple susbstitution.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook