# PRE-CAL

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How can I solve this questions and get those answers????
sec 13pi/4=? =>-ã(2)
csc 13pi/4=? =>-ã(2)
sec (-pi/6)=? =>2ã(3)/3

• PRE-CAL -

13/4 = 3 1/4 = 2 + 1 1/4
so twice around + pi + pi/4
which is
45 degrees below -x axis
cos 5 pi/4 = -1/sqrt 2 so sec 5 pi/4 = -sqrt 2

the others are similar
Just remember once all the way around is 2 pi and halfway around is pi

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