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: U substitution with definite integral

  1. Feb 16, 2012 #1


    User Avatar

    1. The problem statement, all variables and given/known data
    make a u- substitution and integrate from u(a) to u(b)

    2. Relevant equations
    ∫[0,1] √(t^5+2t) (5t^4+2) dt

    3. The attempt at a solution
    u= t^5+2t du= 5t^4+2

    u(1)=2 u(0)=0

    ∫[0,1] √(u) du

    (2/3)(u)^3/2+c l[0,2]

    (2/3)( 0^5+2(0))^3/2- (2/3)(2^5+2(2))^3/2
    0+ 24^3/2

    the textbook answer is 2√3 but I don't know where I messed up
  2. jcsd
  3. Feb 16, 2012 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    u(1)=(1)5 +2(1) = 3 not 2 .
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook