Question 1028474
solve the logarithmic equation algebraically.
 
e^x + e^-x = 4
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Multiply thru by e^2
e^(2x) + 1 = 4e^x
e^(2x) - 4e^x + 1 = 0
Now it's quadratic in e^x.
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Or,
e^x + e^-x = 4
(e^x + e^-x)/2 = 2
sinh(x) = 2
x =~ 1.443635