co·​tan·​gent | \ (ˌ)kō-ˈtan-jənt How to pronounce cotangent (audio) , ˈkō-ˌtan- \

Definition of cotangent

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 : 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

First Known Use of cotangent

1635, in the meaning defined at sense 1

History and Etymology for cotangent

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

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The first known use of cotangent was in 1635

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Cite this Entry

“Cotangent.” Dictionary, Merriam-Webster, Accessed 18 May. 2021.

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Britannica English: Translation of cotangent for Arabic Speakers Encyclopedia article about cotangent

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