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: Help with a Derivative

  1. Jul 2, 2012 #1
    1. The problem statement, all variables and given/known data
    I need to find the derivative of y = (3e^x) + [4 / x^(1 / 3)].

    2. Relevant equations
    My book lists the answer as y' = (3e^x) - (4 / 3)x^-(4 / 3).

    Is the book incorrect, or is there something more I can do to the problem to get the book's correct answer? Please tell me exactly what it is they do to get the aforementioned answer.

    ^ see my answer below.

    3. The attempt at a solution
    I found y' = [(9e^x)(x^(3 / 4)) - 4] / [3x^(3 / 4)]. The same way it's been found here:
  2. jcsd
  3. Jul 2, 2012 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    It might help you to simplify the original problem to this before you differentiate$$
    y = 3e^x +4 x^{-\frac 1 3}$$
  4. Jul 2, 2012 #3
    Thanks. I understand now.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook