Questions: Find the exact value of the expression.
sin^(-1)(cos(3π/4))
Select the correct choice and fill in any answer boxes in your choice below
A. sin^(-1)(cos(3π/4))= □
(Simplify your answer. Type an exact answer, using π as needed. Use integers or fractions for any numbers in the expression.)
B. There is no solution.
Transcript text: Find the exact value of the expression.
\[
\sin ^{-1}\left(\cos \frac{3 \pi}{4}\right)
\]
Select the correct choice and fill in any answer boxes in your choice below
A. $\sin ^{-1}\left(\cos \frac{3 \pi}{4}\right)=$ $\square$
(Simplify your answer. Type an exact answer, using $\pi$ as needed. Use integers or fractions for any numbers in the expression.)
B. There is no solution.
Solution
Solution Steps
To solve the expression \(\sin^{-1}(\cos \frac{3\pi}{4})\), we need to find the angle whose sine is equal to the cosine of \(\frac{3\pi}{4}\). First, calculate \(\cos \frac{3\pi}{4}\). Then, determine the angle in the range \([- \frac{\pi}{2}, \frac{\pi}{2}]\) that has this sine value.
Step 1: Calculate \(\cos \frac{3\pi}{4}\)
We start by calculating the cosine of the angle \(\frac{3\pi}{4}\):
\[
\cos \frac{3\pi}{4} = -\frac{\sqrt{2}}{2}
\]
Step 2: Find \(\sin^{-1}(-\frac{\sqrt{2}}{2})\)
Next, we need to find the angle whose sine is \(-\frac{\sqrt{2}}{2}\). The angle that satisfies this condition in the range \([- \frac{\pi}{2}, \frac{\pi}{2}]\) is:
\[
\sin^{-1}\left(-\frac{\sqrt{2}}{2}\right) = -\frac{\pi}{4}
\]
Final Answer
Thus, the exact value of the expression \(\sin^{-1}\left(\cos \frac{3\pi}{4}\right)\) is:
\[
\boxed{-\frac{\pi}{4}}
\]