What is Trigonometry

What is Trigonometry?

In short, trigonometry is the study of triangles because the word itself means the measurement of triangles. Trigonometry essentially focuses on the relationship between the sides of the triangle and the angles between the sides. The subject is primarily based on the right triangle. Therefore, ratio and proportions can play an important role when studying this subject.

In this section, we will cover the basics of trigonometry.

Trigonometry right triangle with sin, cos and tan

The concept above explains SOH CAH TOA

SOH:
This means that sinA is the opposite side (side a) over the hypotenuse side (side c).

SinA is side a over side c

If you were looking for sinB, then it would be side b over side c

CAH:
This means that cosA is the adjacent side (side b) over the hypotenuse side (side c).

CosA is side b over side c

If you were looking for cosB, then it would be side a over side c

TOA:
This means that tanA is the opposite side (side a) over the hypotenuse side (side c).

TanA is side a over side c

This also means sinA over cosA

If you were looking for tanB, then it would be side b over side c

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