**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)

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Well done !

Good observation a(a+b) = b^2 which is the key leads to solving quadratic equation in (a/b).

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I have liked the identity a(a+b)=b2. explain more

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Note that both and are equal to !

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Reblogged this on Project ENGAGE.

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