Evaluate cos(90 degrees )

Problem

cos(90)

Solution

1. Identify the angle on the unit circle. The angle 90 corresponds to the positive y-axis.

2. Determine the coordinates of the point on the unit circle at 90 The coordinates are (0,1)

3. Apply the definition of the cosine function. On the unit circle, cos(θ) is equal to the x-coordinate of the point.

4. Extract the x-coordinate from the point (0,1) which is 0

Final Answer

cos(90)=0

Want more problems? Check here!