There are many trigonometric identities. Most do not have specific names.
Verify the identity
How do you begin when both sides look complicated?
It often is easier to collapse a difference (or sum) into a product than to expand a product into a difference.
You can use trigonometric identities to simplify trigonometric expressions.
What is a simplified trigonometric expression for
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Write the expression. Then replace
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Replace
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Simplify. | |
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