unit circle

American  

noun

Mathematics.

1. a circle whose radius has a length of one unit.

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Etymology

Origin of unit circle

First recorded in 1950–55

Example Sentences

We have previously defined the sine and cosine of an angle in terms of the coordinates of a point on the unit circle intersected by the terminal side of the angle:

From Textbooks • Dec. 1, 2021

If the angle is not one of the special angles on the unit circle, use a calculator and round to three decimal places.

From Textbooks • Dec. 1, 2021

In Example 6.25, what if we had oriented the unit circle clockwise?

From Textbooks • Mar. 30, 2016

Let F = 〈 − y, x 〉 be the vector field from Example 6.16 and let C represent the unit circle oriented counterclockwise.

From Textbooks • Mar. 30, 2016

Evaluate the integral ∬ ⎛1 − x2 − y2⎞dA where R is the unit circle on the xy -plane.

From Textbooks • Mar. 30, 2016