Evaluate each of the following:

The value of sec is –√2.


The question becomes sec–1(–√2).


Let sec–1(–√2) = y


sec y = –√2


= – sec = √2


= sec


= sec


The range of principal value of sec–1is [0, π]–{}


and sec = –√2


The principal value of sec–1(–√2) is .


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