math
posted by Heather .
solve the following exponential equation
e^x4=e^x
when I work i get
xIn(u)
is this correct

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
u4 = 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)