You can put this solution on YOUR website! e^x-12e^(-x)-1=0
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e^x -12/e^x -1 = 0
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Multiply thru by e^x to get:
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e^(2x) - 12 - e^x = 0
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This is a quadratic in e^x:
Let e^x = w
Substitute to get:
w^2 -w - 12 = 0
Factor:
(w-4)(w+3) = 0
Positive solution:
w = 4
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So, e^x = 4
x = ln(4)
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Cheers,
Stan H.