EXAMPLE 1
Evaluate
trigonometric functions given a point
Let (–4, 3) be a point
on the terminal side of an angle θ in standard
position. Evaluate the six trigonometric functions of θ.
SOLUTION
Use the
Pythagorean theorem to find the value of r.
x2 + y2
√
r
=
(–4)2 + 32
√
=
=
25
√
= 5