Solving a hard equation

[mathrocks]

I have the given equation: (6^x+6^-x)/6 = 2. How do you solve this?

[arildno]

1. Multiply your equation with 6^{x}
2. You have now a quadratic equation in the unknown y=6^{x}
As an alternative, use the identity:
Cosh(t)=\frac{e^{t}+e^{-t}}{2}