Trigonometry

Trigonometry is the study of triangles, their angles, areas and lengths. Right angle triangles and Pythagoras Theorem are the main topics.

An angle of elevation is the angle above the horizontal

The angle of depression is the angle below the horizontal

The Triangle

The sides that make up the right angle of a triangle are called the legs.

the side opposite the right angle is called the hypotenuse.

The Theorem of Pythagoras

a²+b²=c²

c is always the hypotenuse

SOH-CAH-TOA

SOH

SinA = opp/hyp

CAH

CosA = adj/hyp

TOA

TanA = opp/adj

Finding Length of a Side when a given a side and an angle

When given a side and an angle you can find the length of remaing sides. Use either SOH CAH or TOA depending on what your given and what your solving for.

Finding Angles

To find the measure of an angle use sin cos or tan -1.