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 .


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