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noun co·tan·gent \(ˌ)kō-ˈtan-jənt, ˈkō-ˌ\

Definition of cotangent

  1. 1 :  a trigonometric function that for an acute angle is the ratio between the leg adjacent to the angle when it is considered part of a right triangle and the leg opposite

  2. 2 :  a trigonometric function cot θ that is equal to the cosine divided by the sine for all real numbers θ for which the sine is not equal to zero and is exactly equal to the cotangent of an angle of measure θ in radians

Origin and Etymology of cotangent

New Latin cotangent-, cotangens, from co- + tangent-, tangens tangent

First Known Use: 1635

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