-128 degrees has a reference angle of what?
It depends. Where zero is is arbritary. In polar coordinates, and geographical coordinates, zero is Upward (North), and clockwise is positive. In Tensors, zero often To the Right, and counterclockwise is positive. In HS algebra, zero angle is often along the x axis, and moving counterclockwise is positive. One has to keep in mind the decision on directions will impact vector cross product operations.
To determine the reference angle of -128 degrees, we need to understand the concept of reference angles.
A reference angle is the positive acute angle between the terminal arm of an angle and the x-axis in standard position. In standard position, the initial side of the angle lies along the positive x-axis, and the terminal arm rotates counterclockwise.
In this case, -128 degrees is measured in a counterclockwise direction, so we need to find the positive acute angle that is equivalent.
To find the positive acute angle, we can use the following steps:
1. Start with the given angle of -128 degrees.
2. Add 360 degrees to the angle to make it positive. (-128 + 360 = 232 degrees)
3. Since the reference angle needs to be acute, we consider the smaller angle between the positive x-axis and the terminal arm.
4. Subtract the acute angle from 180 degrees to get the reference angle. (180 - 232 = -52 degrees)
Therefore, the reference angle for -128 degrees is 52 degrees.