Question

Hi, can you help me explain the difference between cos, sec, and tan?

Answer 1

Let's differentiate betweeen cos, sec and tan.

The cos, sec and tan are trigonometri functions

• cos

Cos is the short form for cosine.

The cosine of an angle can be said to be the complementary of the angle.

The complement of an angle is the angle subtracted from 90 degrees.

It can also be said to be the ratio of the side adjacent to an acute angle to the hypotenuse in rigt triangle.

`\cos \theta=\frac{\text{adjacent}}{\text{hypotenuse}}`

• Sec.

Sec is the short form for Secant.

It is the reciprocal of cosine.

Given that cosine is the ratio of the adjacent to the hypotenuse, the secant will be the ratio of the hypotenuse to the adjacent.

`\sec \theta=\frac{\text{hypotenuse}}{\text{adjacent}}`

• tan:

tan is the short form for tangent.

Tangent is the ratio of the side opposite the angle to the adjacent side in a right triangle.

`\tan \theta=\frac{opposite}{\text{adjacent}}`