Multiple Angle Formulas
Proposition (Multiple Angle Formulas) The following formulas hold for all angles
and
where the functions are defined.
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Example (Multiple Angle Formulas) Find the exact value of
given
and
is in quadrant 3.
Solution. We have,
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Example (Multiple Angle Formulas) Find the exact value of
given
and
is in quadrant 3.
Solution. Since
and
is in quadrant 3, we have
and thus
so
Therefore,
![multiple angle formulas _gr_21.gif]](pages/multiple-angle-formulas/Images/multiple-angle-formulas_gr_21.gif)
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Example (Multiple Angle Formulas) Prove the trigonometric identity:
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Solution. We have,
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Example (Multiple Angle Formulas) Solve the equation
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Solution. Let
be any integer. We have,
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and
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and
Multiple Angle Formulas
Published by Library of Math -- Online math organized by subject into topics.
Written by Smith, David A.
http://www.libraryofmath.com/multiple-angle-formulas.html


