1. Warm Up Use Pythagorean theorem to solve for x. 1. 2.
Simplify the following radicals.

2. Right Triangle Trig and Angle Measures

3. Right Triangle Trig Ratios

4. Find the exact values of the six trig functions of 8 17
Sketch a right triangle corresponding to the trig ratio given. Use it to find the other five trig ratios.

5. Examples
Let (6, 8) be a point on the terminal side of . Find all six trig ratios.

6. Examples (cont.)
Let (-5, -12) be a point on the terminal side of . Find all six trig ratios.
Let (-4, 0) be a point on the terminal side of . Find all six trig ratios.

7. Examples (cont.)
Find the values of the 6 trig functions of .

8. What quadrant are you in if…

9. Positive and negative angles
An angle is formed by the rotation of a ray about its endpoint. The starting position is the initial side and the position after rotation is the terminal side.
Standard Position
Positive and negative angles

10. Angle measurements
Radian: one radian is the measure of the central angle that intercepts an arc which is equal to the radius of the circle.
Degrees Minutes Seconds

11. Practice…
Determine the quadrant in which the terminal side of the angle lies and sketch the angle in standard position.
100○
-290○50’
9π/5
-2.5
5) Change ○ to degrees, minutes, seconds.
6) Change -175 ○ 30’ 45” to decimal degrees.

12. Angles in standard position whose terminal sides coincide are called co-terminal angles.
Determine two coterminal angles (one negative and one positive) for each given angle.
140○
3π/7

13. Changing radians to degrees and degrees to radians

14. Practice
In #s 1 – 4, Find all 6 trig ratios from the given information. 1.
2. (6, -6)
3. (-1, -2)
cosθ = -1/2, where θ lies in Quadrant II
Convert 11/15 to degrees.
Convert 300º to radians.  14 18

15. Homework Pg 356 #s 4 – 24 (mult. of 4), Pg 366-7#s 7, 9, 13, 17