Search any question & find its solution
Question:
Answered & Verified by Expert
If $\pi \leq x \leq 2 \pi$, then $\cos ^{-1}(\cos x)$ is equal to
Options:
Solution:
2565 Upvotes
Verified Answer
The correct answer is:
$2 \pi-x$
It is given that $\pi \leq x \leq 2 \pi$
$\begin{aligned}
& \Rightarrow-\pi \geq-x \geq-2 \pi \Rightarrow \pi \geq 2 \pi-x \geq 0 \\
& \Rightarrow \cos ^{-1}\{\cos (2 \pi-x)\}=2 \pi-x
\end{aligned}$
$\begin{aligned}
& \Rightarrow-\pi \geq-x \geq-2 \pi \Rightarrow \pi \geq 2 \pi-x \geq 0 \\
& \Rightarrow \cos ^{-1}\{\cos (2 \pi-x)\}=2 \pi-x
\end{aligned}$
Looking for more such questions to practice?
Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.