What is the exact value of $sec 210$ $sec 210$ ?

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Answer 1 · 2015-05-07T03:33:02

$sec 210 = \frac{1}{cos 210} = \frac{1}{cos (30 + 180)} = \frac{1}{- cos 30} .$ $sec 210 = 1/cos 210 = 1/cos (30 + 180) = 1/(-cos 30) .$

$sin c e (- cos 30) = \frac{- s q r 3}{2}$ $Since (-cos 30) = (-sqr3)/2$ , then

$sec 210 = - \frac{2}{s q r 3} = - \frac{2 . s q r 3}{3}$ $sec 210 = -2/(sqr3) = -(2.sqr3)/3$

What is the exact value of sec 210sec210sec 210?