SOLUTION: e^4X-e^2X-6=0 How do I solve for X using natural logs?

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Question 170635: e^4X-e^2X-6=0
How do I solve for X using natural logs?

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
e^4X-e^2X-6=0
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Let w = e^2x
Substitute to get:
w^2 -w - 6 = 0
(w-3)(w+2) = 0
w = 3 or w = -2
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Solve for "x":
e^2x = 3 or e^2x = -2
Take the natural log to get:
2x = ln3 or 2x = ln(-2)
x = (1/2)ln(3) and there is no ln of a negative number.
x = (1/2)*1.0986122..
x = 0.549306..
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Cheers,
Stan H.