- 13.2 Angles and Angle measurements-HW: pg 713 #'s 27-41 odd, 43, 49, 53
- 13.3 Trigonometric Functions of General Angles-HW: pg 722 #'s 17-21, 25-31, 33-39 ODDS!!
- Also, watch the video on Inverse Trig Functions and try problems pg 749 #'s 6-13 all.
13.2 Angles and Angle Measure
What you'll learn...
- Change radian measure to degree measure and vise versa
- Identify coterminal Angles
Just as we can measure a football field in yards or feet--we can measure a circle in degrees (like the good old days) or in radians (welcome to the big leagues!)
Think about what the word radian sounds like...well, it sounds like 'radius', right? It turns out that a radian has a close relationship to the radius of a circle
Definition of radian(we'll break this down more on this page): a radian is the measure of an angle that, when drawn a central angle of a circle, intercepts an arc whose length is equal to the length of the radius of the circle.
Degrees to radians The general formula for converting from degrees to radians is to simply multiply the number of degree by Π /180°
- Example 1:
Convert 200° into radian measure:
200° (Π/180°) = 200/180Π radians or 3.49 radians - Example 2:
Convert 120° into radian measure:
120° (Π/180°) = (2/3)Π radians = 2.09 radians
Radians to degrees
The general formula for converting from degrees to radians is to simply multiply the number of degree by 180°/(Π)
- Convert 1.4 radians into degrees: 1.4 (180°/Π) = 80.2 °
13.3 Trigonometric Functions of General Angles
Example 2: Use a Reference Angle to find a Trigonometric Value
13.7 Inverse Trigonometric Functions
What you'll learn...
* Solve Equations using Inverse Trigonometric Functions
* Find values of trigonometric expressions
Practice Quiz
