SOLUTION: If e^ { 2 x } - 1 e^ { x } = + 2

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Question 507912: If e^ { 2 x } - 1 e^ { x } = + 2
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
solving for x
e^ { 2 x } - 1 e^ { x } = + 2
e^2x-e^x-2=0
let u=e^x
u^2=e^2x
u^2-u-2=0
(u-2)(u+1)=0
u=2
or u=-1
..
for u=-1
e^x≠-1
reject
..
for u=2
e^x=2
take ln of both sides
lne^x=ln2
x=.6931