How do you find the exact value for $sec 315$ ?

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Answer 1 · 2015-10-10T14:14:39

Find sec 315

Ans: $sqrt2$

$sec (315) = 1/(cos 315).$ Find cos (315)
$cos (315) = cos (-45 + 360) = cos (-45) = cos (45) = sqrt2/2$

Therefor, $sec 315 = 1/(cos 45) = 2/sqrt2 = sqrt2$

How do you find the exact value for sec 315sec 315?