Answer:
4a.
4b.
Explanation:
The expression for problem (4a) is
Least Common Multiplier of the denominators. The easiest way to do this is to simply multiply the denominators together.
LCM of
But first, let's simplify the two expressions by factoring
and
Multiply the coefficients 2 and -3 to get -6 and find an expression that appears in both.
This gives LCM as
For
since
since
We get
Since the denominators are the same, we can apply the fraction rule:
Numerator
becomes
=
Therefore the expression result is
Part (b)
Note that
So the LCM is
=
Multiply the second term in the expression by
and subtract from the first term
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