SOLUTION: how do you solve for x in terms of e or ln in this example {{{e^(2x)-2e^x-15=0}}}

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Question 560418: how do you solve for x in terms of e or ln
in this example
e%5E%282x%29-2e%5Ex-15=0
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
this is a quadratic in e^x ___ (e^x)^2 - 2(e^x) - 15 = 0

factoring ___ [(e^x) - 5][(e^x) + 3] = 0

e^x - 5 = 0 ___ e^x = 5 ___ x = Ln(5)

e^x + 3 = 0 ___ e^x = -3 ___ logarithms (natural or otherwise) are not defined for negative arguments