Question

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

Answer 1

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.