Question

1. Find the value of sec Θ if tan Θ = -2 90° ≤ Θ ≤ 180°

a. -√5
b. √5
c. -5
d. 5

2. Find the value of cos Θ if sec Θ = 5/3 270 ≤ Θ ≤ 360°
cos =

Answer 1

9514 1404 393

Answer:

1. (a) -√5

2. 3/5

Explanation:

1. sec²(θ) = tan²(θ) +1

sec²(θ) = (-2)² + 1 = 5

sec(θ) = ±√5

In the second quadrant, secant is negative, so ...

sec(θ) = -√5

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2. cos(θ) = 1/sec(θ)

cos(θ) = 1/(5/3)

cos(θ) = 3/5