Question

(e^x + e^-x)/2=1

Answer 1

Spamming the board while using different screen names is unacceptable, as is posting all your homework problems, but giving no indication of what you know or have done.

Answer 2

let e^x = y
y + 1/y = 2
y^2 - 2y + 1 = 0
(y-1)^2 = 0
y = 1

so e^x = 1 ----> x = 0