What is the unit circle and why is it useful?
In: Mathematics
A unit circle is a circle whose radius is exactly 1 unit. They’re not really more useful than any other circle, but they are more convenient and easier to work with than any other circle. Because the radius is 1, you can just drop the r in most of the circle’s formulas (area, perimeter, etc). When using trig, functions, you can use the results as-is without having to multiply by r (effectively, the trig. functions are based on right triangles whose hypotenuse is exactly 1 unit. When applying them to arcs, the radius of the circle acts as the hypotenuse. Unit circle = unit hypotenuse = easy trig. functions).
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