Rationalizing the Denominator
If an expression such as
appears in a denominator,
we can multiply both the numerator and denominator by its conjugate
to get a rational number in the denominator.
Example 1
Rationalizing the denominator using conjugates
Write in simplified form.

Solution
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Multiply the numerator and denominator by
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Simplify. |
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Multiply the numerator and
denominator by
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Helpful hint
The expressions in Example 1
are the types of expressions
that you must simplify when
learning the quadratic formula.
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