**Question:**

Given , find the value of .

**Solution:**

Working with logarithm is tricky, we try to **transform the question to an exponential question**.

Let

Then, we have

.

Here comes the** critical observation**:

Observe that .

Divide throughout by , we get .

Hence, .

Solving using quadratic formula (and reject the negative value since and has to be positive for their logarithm to exist),

We get .

If you have any questions, please feel free to ask me by posting a comment, or emailing me.

(I will usually explain in much more detail if I teach in person, than when I type the solution)