noun
cosine
KOH-sine/ˈkəʊsaɪn/
A trigonometric function giving the ratio of the adjacent side to the hypotenuse for an angle in a right triangle.
The angle's cosine equals the adjacent side's length divided by the hypotenuse's length.
Etymology
The pieces mean “sine of the complement”: an angle’s cosine is the sine of the angle that completes a right angle with it. This makes the adjacent side serve as the complementary angle’s opposite side.
In context
what's X relative to 60 it's the adjacent relative to 60 so I have to use cosine so this becomes cos of 60 degrees is equal to adjacent adjacent X over ten
More examples
- Divide the adjacent side by the hypotenuse to find the angle's cosine.
- Set your calculator to degrees before finding the cosine of 30 degrees.
- Multiply the hypotenuse by the angle's cosine to get the adjacent side's length.
Forms
cosine · cosines