Use the equation below to answer the question

Question

cos(θ)=-9/41

the unit of θ is radians. Which assumption is necessary to state that sin(θ)=-40/41

 

a)the angle is located in quadrant I

b) located in quad II

c) located in quad III

d) located in quad IV

Answer 1

Since cosθ < 0 and sinθ < 0, θ lies in Quadrant 3.  

Answer 2

Correction. Quadrant III.

For both sine and cosine of θ to be negative, the angle must be located in Quadrant IV.