Question

Read the section and make your own summary of the material.

Short answer

The trigonometry identities use to find the sides and angle of the triangle.

Step-by-step solution

Introduction

In this section learn about trigonometry and the Pythagorean theorem. It is applicable in a right-angle triangle. There are two sides and one hypotenuse. The hypotenuse is the longest side of the triangle.

Explanation

In triangle \(ABC\) , \(\angle B=90^\circ\)

There are trigonometry identities:

\(\begin{align*}\bullet &&\sin^2C+\cos^2C=1\\\bullet &&\sec^2C=1+\tan^2C\\\bullet &&\csc^2C=1+\cot^2C\end{align*}\)

\(\sin C=\frac{c}{b}\)

\(\cos C=\frac{a}{b}\)

\(\tan C=\frac{c}{a}\)

Using this identity relation between \(\sin C,\cos C\) and \(\tan C\).

\(\tan C=\frac{\sin C}{\cos C}\)