solve the following exponential equation

Question

e^x-4=-e^-x

when I work i get

x-In(u)
is this correct

Answer 1

We left off at that point in my previous answer. Apparently you did not do much work thereafter.

If you let u=e^x, your equation becomes

u-4 = -1/u
u^2 - 4u + 1 = 0
u = 2±√3

since u=e^x, x=ln(u)
so, x = ln(2+√3) or ln(2-√3)