Definition, Meaning & Synonyms
cos
Mathematical function
/kɒs/
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Definition
The cosine of an angle in a right triangle is the ratio of the length of the adjacent side to the length of the hypotenuse.
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Examples
- The cosine of 0 degrees is 1.
- In a right triangle, if one angle is 30 degrees, the cosine of that angle is √3/2.
- Calculating the cos of an angle can help find the lengths of sides in trigonometric problems.
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Meaning
In trigonometry, ‘cos’ refers to a basic function that is used to relate the angles of a triangle to the lengths of its sides.
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Synonyms
- Cosine