How do you give the exact value of $sec^2 300-2cos^2 150+tan 45$ ?

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Answer 1 · 2015-02-15T04:44:03

$sec^2(300^o) = (1 / (cos^2(300^o)))$
$cos(300^o) = cos(-60^o) = cos(60^o) = 1/2$
$cos^2(300^o) = 1/4$
$sec^2(300^o) = 4$

$cos(150^o) = - cos(30^o) = - sqrt(3)/2$
$cos^2(150^o) = 3/4$
$2 cos^2(150^o) = 3/2$

$tan(45^o) = 1$

$sec^2(300^o) - 2 cos^2(150^o) + tan(45^o)$
$= 4 - 3/2 + 1$
$= 3 1/2$

How do you give the exact value of sec^2 300-2cos^2 150+tan 45sec^2 300-2cos^2 150+tan 45?