Question 737181
(e^x+e^-x) / 2 = 1


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


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


Let z = e^x


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


(z^2+1)/(2z) = 1


z^2+1 = 2z


z^2-2z+1 = 0


(z-1)^2 = 0


z-1 = 0


z = 1


e^x = 1


Final Answer: e^x = 1