Download Ch 10-2 Angles of Rotation

Chapter 10-2 Angles of Rotation (Day 2)
Obj: Find Reference angles for an angle in standard position.
Determine the values of the trigonometric functions for an angle in standard position
Reference Angle - for an angle 𝜃 in standard position, the reference
angle is the positive acute angle formed by the terminal side of 𝜃 and
the x-axis.
Examples: Find the measures of the reference angle for each given angle (tip…sketch the angle)
𝑎) 150°
𝑏) − 130°
𝑐) 280°
𝑎) −100°
𝑏) − 245°
𝑐) 330°
Determining the value of trigonometric functions for an angle 𝜃 in standard position, use
a point 𝑃 with coordinates (𝑥, 𝑦) on the terminal side of the angle. The distance 𝑟 from
point 𝑃 to the origin is given by √𝑥 2 + 𝑦 2
Example: 𝑃𝑜𝑖𝑛𝑡 𝑃 is a point on the terminal side of 𝜃 in standard position. Find the exact
value of the six trigonometric functions for 𝜃.
𝑎) 𝑃(−4, 3)
(hint: Plot point and sketch a right triangle – find “r”)
𝑏) 𝑃(4, −5)
Homework (day 2) pg 703, 10 – 21, 34 – 41