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Posers and Puzzles

Posers and Puzzles

  1. Subscriber joe shmo On Vacation
    Strange Egg
    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. 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. Subscriber AThousandYoung
    It's about respect
    19 Oct '10 11:17
    The t in the exponent is in the denominator, not the numerator.
  4. Subscriber joe shmo On Vacation
    Strange Egg
    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. Subscriber joe shmo On Vacation
    Strange Egg
    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 member Palynka
    Upward Spiral
    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. Subscriber joe shmo On Vacation
    Strange Egg
    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...