Sum-to-Product Formulas
Proposition (Sum-to-Product Formulas) The following formulas hold for all angles
and
where the functions are defined.
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Example (Sum-to-Product Formulas) Find the exact value of
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Solution. We have,
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Example (Sum-to-Product Formulas) Prove the trigonometric identity:
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Solution. We have,
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![sum to product formulas _gr_16.gif]](pages/sum-to-product-formulas/Images/sum-to-product-formulas_gr_16.gif)
![sum to product formulas _gr_17.gif]](pages/sum-to-product-formulas/Images/sum-to-product-formulas_gr_17.gif)
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Example (Sum-to-Product Formulas) Prove the trigonometric identity:
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Solution. We have,
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![sum to product formulas _gr_22.gif]](pages/sum-to-product-formulas/Images/sum-to-product-formulas_gr_22.gif)
![sum to product formulas _gr_23.gif]](pages/sum-to-product-formulas/Images/sum-to-product-formulas_gr_23.gif)
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Example (Sum-to-Product Formulas) Solve the equation
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Solution. Let
be any integers. We have,
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Example (Sum-to-Product Formulas) Solve the equation
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Solution. We have,
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Sum To Product Formulas
Published by Library of Math -- Online math organized by subject into topics.
Written by Smith, David A.
http://www.libraryofmath.com/sum-to-product-formulas.html


