Find the principal values of each of the following:

cosec–1(–2)


cosec–1–2 = y


cosec y = –2


–cosec y = 2


–cosec = 2


As we know cosec(–θ) = –cosecθ


–cosec = cosec


The range of principal value of cosec–1 is –{0} and


cosec = –2


Therefore, the principal value of cosec–1(–2) is .


1