Question

Determine the sign of sin without using a calculator.
1) positive
2) negative

Answer 1

The sign of the sin function can be determined by understanding its behavior on the unit circle and the quadrant it lies in.

Step-by-step explanation:

The sign of the sin function can be determined by understanding its behavior on the unit circle. On the unit circle, the sin function is positive in the first and second quadrants, and negative in the third and fourth quadrants.

Since the sin function is periodic with a period of 2π, you can determine its sign in any other angle by using the reference angle and the quadrant it lies in.

For example, if you have an angle of 45 degrees (π/4 radians), it lies in the first quadrant where sin is positive.