Question 1088891
find the exact value of the indicated trigonometric function of theta. 

sin theta = -2/5, tan theta > 0 find sec theta
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sin - and tan + --> Q3
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cos = sqrt(1 - sin^2) = -sqrt(21)/5  (cos - in Q3)
sec = 1/cos = -5/sqrt(21)
= -5sqrt(21)/21