1. Subscriberjoe shmo
    Strange Egg
    podunk, PA
    Joined
    10 Dec '06
    Moves
    7733
    18 Oct '10 20:32
    Does anyone see a clear cut solution analytic solution to the following equation?
    I came across it in a homework problem, and couldn't seem to see the path to take. Its too late for the grade, and the course isn't in solving equations, but its troubling me that the writers would leave its solution to approximation methods.

    -10^5*e^(-1/20*t) -10^4*t + 2*10^5 = 0
  2. In Christ
    Joined
    30 Apr '07
    Moves
    172
    19 Oct '10 10:24
    Hate to break it to you, but if this is of the form a*e^x + b*x = c (and I believe it is), then there is no analytical solution.
  3. SubscriberAThousandYoung
    All My Soldiers...
    tinyurl.com/y9ls7wbl
    Joined
    23 Aug '04
    Moves
    24791
    19 Oct '10 11:17
    The t in the exponent is in the denominator, not the numerator.
  4. Subscriberjoe shmo
    Strange Egg
    podunk, PA
    Joined
    10 Dec '06
    Moves
    7733
    19 Oct '10 11:56
    Originally posted by AThousandYoung
    The t in the exponent is in the denominator, not the numerator.
    no, its in the numerator.
  5. Subscriberjoe shmo
    Strange Egg
    podunk, PA
    Joined
    10 Dec '06
    Moves
    7733
    19 Oct '10 11:57
    Originally posted by Jirakon
    Hate to break it to you, but if this is of the form a*e^x + b*x = c (and I believe it is), then there is no analytical solution.
    ok, thanks for the help.
  6. Standard memberPalynka
    Upward Spiral
    Halfway
    Joined
    02 Aug '04
    Moves
    8702
    19 Oct '10 13:47
    Originally posted by joe shmo
    ok, thanks for the help.
    This might interest you:
    http://www.wolframalpha.com/input/?i=-10^5*e^(-1/20*t)+-10^4*t+%2B+2*10^5+%3D%3D+0
  7. Subscriberjoe shmo
    Strange Egg
    podunk, PA
    Joined
    10 Dec '06
    Moves
    7733
    19 Oct '10 16:21
    Originally posted by Palynka
    This might interest you:
    http://www.wolframalpha.com/input/?i=-10^5*e^(-1/20*t)+-10^4*t+%2B+2*10^5+%3D%3D+0
    Indeed it does...

    😉
Back to Top