In this lesson, we will learn the names of the sides of a right triangle (hypotenuse, adjacent, opposite) and how they are used in trigonometry.
Before we study trigonometry, we need to know how the sides of a right triangle are named. The three sides are called hypotenuse, adjacent and opposite sides.
In the following right triangle PQR,
Note: The adjacent and the opposite sides depend on the angle θ . For complementary angle of θ , the labels of the 2 sides are reversed.
Identify the hypotenuse, adjacent side and opposite side in the following triangle:
a) for angle x
b) for angle y
a) For angle x: AB is the hypotenuse, AC is the adjacent side , and BC is the opposite side.
b) For angle y: AB is the hypotenuse, BC is the adjacent side , and AC is the opposite side.
Opposite Sides, Adjacent Sides and Hypotenuse of a Right Triangle.
Definition of Cos, Sin, Tan, Csc, Sec, Cot
Using the Sine Formula (the SOH formula)
The first part of this video will explain the diffremce between the hypotenuse, adjacent and opposite sides of a right triangle. Then it shows how to use the sine formula (the SOH formula)
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