In class and through examples, we talked about how the functions $cos^{-1}x$ and $cos x$ sometimes cancel each other out, but sometimes don't. Explain why the value of $cos^{-1}(cos(\frac{7\pi}{4}))$ cannot be $\frac{7\pi}{4}$, and then find the value of the expression. Show work to support your answer and your reasoning.
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Step 1: The value of cos(cos) cannot be determined directly because the cosine function takes an angle as its input, not another function. Show more…
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