Solving Exponential and Hyperbolic Equations: e^(3x)+sinh(x)=0

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Homework Statement



Solve the following equation for x:

e^{3x}+sinh(x)=0


Homework Equations



None.


The Attempt at a Solution



It the same as:

e^{3x}+\frac{e^{2x}}{2}-\frac{e^{-2x}}{2}=0

Multiply by 2

2e^{3x}+e^{2x}-e^{-2x}=0

Multiply by e^(2x)

2e^{5x}+e^{4x}=1

then I stopped.
 
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I think sinh(x)=\frac{e^{x}}{2}-\frac{e^{-x}}{2}
 
sinh(x) = 1/2(e^x - e^(-x))

Looks to me like you should be able to get a quadratic equation out of that...
 
ohhhh
sorry
:|
I finished it
thanks <3
 
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