Let the left side = y
Take the log base 10 of both sides
The original inequality was
So . Substituting for y
We know that is a negative
number, so when we multiply both sides
of the inequality by it, the inequality
symbol will reverse:
Use a principle of logarithms to rewrite
the right side:
Since raising to the -1 power is the same
as taking the rciprocal, the above becomes:
Since logs base 10 are in ascending order,
That has critical numbers
Put those two values on a number line and
choose a test point in each region to discover that
the solution set is
or
Edwin