Question
Which of the following is the principal value branch of $${\text{cose}}{{\text{c}}^{ - 1}}x\,?$$
A.
$$\left( {\frac{{ - \pi }}{2},\frac{\pi }{2}} \right)$$
B.
$$\left( {0,\pi } \right) - \left[ {\frac{\pi }{2}} \right]$$
C.
$$\left[ {\frac{{ - \pi }}{2},\frac{\pi }{2}} \right]$$
D.
$$\left[ {\frac{{ - \pi }}{2},\frac{\pi }{2}} \right] - \left\{ 0 \right\}$$
Answer :
$$\left[ {\frac{{ - \pi }}{2},\frac{\pi }{2}} \right] - \left\{ 0 \right\}$$
Solution :
Principal value branch of $${\text{cose}}{{\text{c}}^{ - 1}}x$$
$$ = \left[ {\frac{{ - \pi }}{2},\frac{\pi }{2}} \right] - \left\{ 0 \right\}$$