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Is this statement true or not? cos (cos^-1 (2)) = 2 Explain why or why not.

User Gricha
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1 Answer

6 votes

True

1) Let's evaluate that, using one identity for that:


\begin{gathered} \cos (\cos ^(-1)(2))= \\ \cos (\cos ^(-1)(\theta))=\theta \\ \cos (\cos ^(-1)(2))=2 \end{gathered}

2) Since the cosine of the arc cosine (theta) is equal to theta, we can state that this trigonometric equation is true.

3) Hence, that's true.

User Stypox
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