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Find the Zeros of the Equation

  • Thread starter Lord Dark
  • Start date
  • #1
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Homework Statement


i have a problem i tried to solved about 3 days and i couldn't ... here it is :

(exp(x)/x^3)=2x+1

Homework Equations





The Attempt at a Solution


((e^x)/(x^3))=2x+1 > e^x=2x^4+x^3 >> (x=ln(2x^4+x^3) or 2x^4+x^3-e^x=0) ,, is it possible to get the zeros from the 2 solutions without graphing ??
 

Answers and Replies

  • #2
HallsofIvy
Science Advisor
Homework Helper
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There is not going to be any "algebraic" method of solving that. You might be able to put it in terms of the Lambert W function but that's probably not what you want. Generally speaking, equations that involve the unknown variable both inside and outside a transcendental function require either "special functions", such as the Lambert W, or numerical solutions, such as graphing.
 
  • #3
121
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thanks very much :)
 

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