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

Quick question on tables and integration

  1. Mar 6, 2007 #1
    ok so here is the problem


    the table integral I am supposed to use is this

    Is it proper to make my u=x^2 and a=2x^(1/2)
    I am asking because the solution guide tells me to complete the square, and then proceed to pick the u and a
    Last edited by a moderator: Mar 7, 2007
  2. jcsd
  3. Mar 6, 2007 #2
    No. a is assumed to be constant.
  4. Mar 6, 2007 #3
    so if a is any real number i can do this, but if any nonconstant variable is there than I need to find another way? Sorry it has been a while since Ive done this.
  5. Mar 7, 2007 #4


    User Avatar
    Science Advisor
    Homework Helper

    It doesn't matter whether it's "a" or "b", "y", "z",...You integrate wrt "x" and that's all that matters. Don't use tables of integrals, when the integrations can be done explicitely.
  6. Mar 7, 2007 #5
    Yes, you're right. I was being lazy...constant in this context means a does not depend on x.

    Another one of the little nuances in math.
  7. Mar 7, 2007 #6


    User Avatar
    Science Advisor

    I wouldn't consider the definition of "constant" to be a "little nuance"!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook