1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
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: Integration (Substitution)

  1. Sep 6, 2011 #1
    Please help me calculate these integrals.
    Suppose that ∫f(t)dt=11 [0,1]. Calculate each of the following.
    A. ∫f(4t)dt [0,0.25] =

    B. ∫f(1−4t)dt [0,0.25] =

    C. ∫f(3−8t)dt [0.25,0.375] =

    I did the first one and I beleive is right and I try to do the 2nd and 3rd one similarily and can't get them .:uhh:
    du=4dt, or
    ∫f(4t)dt [0,0.25]
    =∫f(u)(1/4)du [0,4*0.25]
    =(1/4)∫f(u)du [0,1]
  2. jcsd
  3. Sep 6, 2011 #2
    The second one is almost exactly the same. What substitution would you try??
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook