Establish the Identity $$\sin ( x + y ) - \sin ( x - y ) = 2 \cos x \sin y$$

question 162

Essay

Establish the identity.
- $$\sin ( x + y ) - \sin ( x - y ) = 2 \cos x \sin y$$

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Definitions:

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Archduke of Austria-Este whose assassination in Sarajevo in 1914 sparked the beginning of World War I.

Serbian Nationalist

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Greater Serbia

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