Trigonometry An Introduction

hypotenuse

opposite

adjacent

tangent

opposite

hypotenuse

sine

adjacent

a

$$\frac{adjacent}{hypotenuse}$$  

$$\frac{opposite}{adjacent}$$  

$$\frac{opposite}{hypotenuse}$$  

$$\frac{adjacent}{opposite}$$  

a

b

c

d

tangent ratio

cosine ratio

sine ratio

Pythagoras

$$\frac{9}{12}$$  

$$\frac{4}{5}$$  

$$\frac{3}{5}$$  

$$\frac{3}{4}$$  

$$\frac{\tan\ 23\degree}{5.7}$$  

$$\frac{5.7}{\tan\ 23\degree}$$  

$$5.7\ \times\tan\ 23\degree$$  

$$\frac{\tan\ 23\degree\ \times\ 5.7}{2}$$  

$$\frac{5}{3}$$  

$$\frac{20}{15}$$  

$$\frac{3}{4}$$  

$$\frac{4}{3}$$