There are several “Laws” of Logarithms. They are:

The
bases seem to cancel in the first expression and to swap with the
argument in the second.

Ie
we eliminate a log by raising the base to the power of both sides.
Problems involving logs usually reduce to a simple linear or
quadratic equation.
Example:

Use
the first rule to obtain a single log.

Use
the sixth rule to eliminate the log.

Expand
this and simplify.

Factorise
and solve.

Example:

We
must make the bases the same for both logs. We can do this with the
second case of the fifth rule:

We
have,

Substitute

to give

and
multiply throughout by p:

Subtract

and
simplify to give,

then
factorise.

So,

or
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