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: Simple/annoying derivative

  1. Sep 4, 2006 #1
    Could som1 please explain how to derive y = x^(x^2-7):yuck:

    I started using the chain rule but got stuck wif the x base.

    thanx in advance
  2. jcsd
  3. Sep 4, 2006 #2


    User Avatar
    Science Advisor

    Do you mean "find the derivative"? (Yes, "derive f(x)" can mean that but often it means "derive this formula".)

    Use "logarithmic differentiation". (In fact, I would expect a problem like this to be in a section of the book titled "logarithmic differentiation"!)

    If [itex]y= x^{x^2- 7}[/itex] then [itex]ln(y)= (x^2- 7)ln(x)[/itex].
    Can you differentiate both sides of that? Then solve for dy/dx.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Similar Threads for Simple annoying derivative Date
What went wrong with my simple differential equation? Jan 19, 2018
Simple integration to find area Nov 21, 2017
Simple set theory question Sep 11, 2017
Simple but annoying characteristic of congruences Feb 25, 2013