How do you use $sintheta=1/3$ to find $sectheta$ ?

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Answer 1 · 2018-02-19T17:49:44

$sintheta=1/3$

by the identity, we know, $cos^2x +sin^2x=1$

therefore, $sin^2theta= 1- cos^2theta$

$cos^2theta= 1- (1/3)^2$

$cos^2theta= 1- (1/9)$

$cos^2theta= 8/9$

$costheta= +-sqrt(8/9)= +-(2sqrt2)/3$

now, we know, $secθ=1/costheta$

$secθ=+-3/(2sqrt2)$

How do you use sintheta=1/3sintheta=1/3 to find secthetasectheta?