How do I find the value of sec -3pi/4?

2 Answers
Aug 22, 2015

sec((-3pi)/4) = -sqrt(2)

Explanation:

sec = ("hypothenuse")/("adjacent side")
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Aug 22, 2015

Find sec ((-3pi)/4)

Ans: - sqrt2

Explanation:

Another way to find sec((-3pi)/4)

sec ((-3pi)/4) = 1/sin ((-3pi)/4). Find sin ((-3pi)/4)

On the trig unit circle,
sin ((-3pi)/4) = sin (-pi/4) = - sin (pi/4) = - sqrt2/2
Therefor:
sec ((-3pi)/4) = (1/sin) = -2/sqrt2 = - sqrt2