1. January 19 th in your BOOK, 4.2 copyright2009merrydavidson

2. Special Right Triangles S O H C A H T O A

3. y x r Reciprocal functions Parent functions

4. Reciprocal Identities Memorize these 11 identities for a quiz SOON!!!

5. Look at your unit circle now… cosine sine Check out the Pythagorean Identities

6. Evaluating Trig Functions: 1: Find the six trig. values for 300 . sin 300 o = csc 300 o = cos 300 o = sec 300 o = tan 300 o =cot 300 o = Use your Plate, find the angle, evaluate. Rationalize the denominator as needed.

7. Evaluating Trig Functions: 2: Find the six trig. values for -5  /4. sin = csc = cos = sec = tan =cot = Use your Plate, find the angle, evaluate. Rationalize the denominator as needed.

8. Find the sine of the angles listed. 30 o =390 o =-330 o = What is the NAME of the type of these 3 angles? What conclusion can you make? Co-terminal angles have the same trig values. It takes 360 o to get to the same trig value, thus the PERIOD for the sine and cosecant function is 360 o co-terminal angles

9. Find the cosine of the angles listed. 60 o =420 o =-300 o = It takes 360 o to get to the same place, thus the PERIOD for the cosine and secant function is 360 o or.

10. Find the tangent of the angles listed. 45 o =225 o =-135 o = It takes 180 o to get the same trig value, thus the PERIOD for the tangent and cotangent function is 180 o.

11. Summary of Period sin/csc/cos/sec have a period of 360 o. tan/cot have a period of 180 0. BE CAREFUL TO NOT USE CAPITAL LETTERS. WE WILL LEARN THAT LATER

12. y = sin x Is this an even or odd function? y = csc x is also odd.

13. y = cos x Is this an even or odd function? y = sec x is also even

14. -360-270 -180 -90 0 90 180 270 360 y = tan x Is this an even or odd function? y = cot x is also odd

15. Now look at the even/odd Identities What does this mean????

16. Trig Identities f(x) = cos xf(x) = sin x EVEN ODD

17. Problems 1)If sin (t) = ¼, find sin (-t). 2)If sin (t) is 3/8, find csc (-t). 3) If cos (t) = -3/4, find cos(-t). -1/4 If sin (t) is 3/8, then csc (t) = 8/3. We want to find csc (-t) which is the opposite of csc (t) = -8/3. cos(t) = cos(-t) so = -3/4

18. Trig Identities f(x) = tan x ODD If tan (t) = 2/3 find tan (-t). -2/3

19. HW: WS 6-4