7-5 Multiplying and Dividing Radicals Day 2

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7-5 Multiplying and Dividing RadicalsDay 2

• To divide radicals
• divide the coefficients
• divide the radicands if possible
• rationalize the denominator so that no radical
  remains in the denominator

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We need to rationalize the denominator by
multiplying the fraction by a number that will
give us a perfect square under the radical in the
denominator this will eliminate the radical in
the denominator.
42 cannot be simplified, so we are finished.
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This can be divided which leaves the radical in
the denominator. We need to rationalize the
denominator by multiplying the fraction by a
number that will give us a perfect square under
the radical in the denominator this will
eliminate the radical in the denominator.
4
This cannot be divided which leaves the radical
in the denominator. We need to rationalize the
denominator by multiplying the fraction by a
number that will give us a perfect square under
the radical in the denominator this will
eliminate the radical in the denominator.
Reduce the fraction.
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Example 8 1
Rationalize the denominator of
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Example 8 2
Rationalize the denominator of
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Example 9 1
To rationalize the denominator of a fraction with
square roots in a binomial in the denominator ,
you must multiply by the conjugate. Use FOIL to
simplify the denominator. The conjugate of a b
is a b / The conjugate of a b is a
b Rationalize the denominator
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Example 9 2
To rationalize the denominator of a fraction with
square roots in a binomial in the denominator ,
you must multiply by the conjugate. Use FOIL to
simplify the denominator. The conjugate of a b
is a b / The conjugate of a b is a
b Rationalize the denominator
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Homework
Pg 479 52, 56, 60, 62, 70, 72, 80, 82, 84, 90,
92, 102