\"\"

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The functions are \"\" and \"\".

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Graph:

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Graph the functions \"\" and \"\":

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\"\"

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Observe the graph:

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The both functions are equal for all real numbers.

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\"\"

\

The functions are  \"\" and \"\".

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Consider the function \"\".

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Trigonometry identitiec: \"\".

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\"\"

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\"\"

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Hence  \"\".

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\"\"

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The both functions are equal for all real numbers.