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: Exponential and logarithmic properties

  1. May 19, 2006 #1
    Hi. I'm having trouble solving for t:

    1180 = 98t + 1080e^(-t/10)

    I know basic properties but I think I am not remembering some idea or specific property to be able to solve this. Thank you for any help.
  2. jcsd
  3. May 19, 2006 #2


    User Avatar
    Science Advisor

    Since the variable, t, appears both "inside" an exponential and "outside" there is no elementary function that will reduce that equation. You might look at "Lambert's W function" (check
    http://en.wikipedia.org/wiki/Lambert's_W_function) which is defined[\b] as the inverse of the function f(x)= xex.
    A variation of that will "solve" your equation.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook