Final answer:
To determine the quadrant in which an angle θ lies, consider the signs of the x-coordinate and y-coordinate.
Step-by-step explanation:
In order to determine the quadrant in which an angle θ lies, we need to consider the signs of the x-coordinate and y-coordinate of the point on the unit circle determined by the angle.
If the x-coordinate is positive and the y-coordinate is positive, then the angle θ lies in the first quadrant. If the x-coordinate is negative and the y-coordinate is positive, then the angle θ lies in the second quadrant.
If the x-coordinate is negative and the y-coordinate is negative, then the angle θ lies in the third quadrant. If the x-coordinate is positive and the y-coordinate is negative, then the angle θ lies in the fourth quadrant.