Holt Geometry 3-1 Lines and Angles  Paper for notes  Pearson 13.2

Holt Geometry 3-1 Lines and Angles TOPIC: 13.2 Angles and the Unit Circle Name: Daisy Basset Date : Period: Notes Objective: Interpret trigonometric functions as radian measures of angles traversed counterclockwise around the unit circle.

Holt Geometry 3-1 Lines and Angles Key Concept  Cosine & Sine of an Angle (draw the picture)

Holt Geometry 3-1 Lines and Angles Vocabulary  Standard Position  Initial & Terminal sides  Coterminal Angle  Unit Circle

Holt Geometry 3-1 Lines and Angles  Notes 13.2  13.2 handout  Calculator

Holt Geometry 3-1 Lines and Angles 1. Use the notes handout to find the measure of each angle.

Holt Geometry 3-1 Lines and Angles A. 90º

Holt Geometry 3-1 Lines and Angles B. -135º -90º -45º

Holt Geometry 3-1 Lines and Angles C. 225º 180º 45º

Holt Geometry 3-1 Lines and Angles 2. What is the sketch of each angle in Standard Position?

Holt Geometry 3-1 Lines and Angles A. 36º 45º

Holt Geometry 3-1 Lines and Angles B. 315º 45º  180º  90º

Holt Geometry 3-1 Lines and Angles C. -150º -135º

Holt Geometry 3-1 Lines and Angles D. 85º 45º

Holt Geometry 3-1 Lines and Angles Summary What does the sign on an angle measure mean?

Holt Geometry 3-1 Lines and Angles Hmwk 13.2 A: Practice: 7, 8, 13 – 17, Work on the Study Plan

Holt Geometry 3-1 Lines and Angles Hmwk 13.2 A: Practice: 7, 8, 13 – 17,

Holt Geometry 3-1 Lines and Angles  Notes Notes Handout  Calculator

Holt Geometry 3-1 Lines and Angles 3. Which of the following angles is not coterminal with the other three? A.300ºB. -60º C. 60ºD. -420º

Holt Geometry 3-1 Lines and Angles A.300º B. -60º C. 60º D. -420º 

Holt Geometry 3-1 Lines and Angles 4. Which of the following angles is not coterminal with the other three? A.-315ºB. 45º C. 315ºD. 405º

Holt Geometry 3-1 Lines and Angles Remember: Two angles are coterminal if they differ by a multiple of 360º. -315º- 45º= -315º-315º= -315º-405º= -360º -630º -720º ______ is not coterminal. C. 315º -315º 45º 315º 405º 

Holt Geometry 3-1 Lines and Angles 5. What are the cos  and sin  for the following angles?

Holt Geometry 3-1 Lines and Angles cos 90º = sin 90º = (x, y) = (, ) cos  sin  0 1 A.

Holt Geometry 3-1 Lines and Angles cos -180º= sin -180º= (x, y) = (cos , sin  ) 0 B.

Holt Geometry 3-1 Lines and Angles Summary Without graphing, how can you determine if two angles are coterminal?

Holt Geometry 3-1 Lines and Angles Hmwk 13.2 B: Practice: 18 – 25, 27, 29, 31, 33 Work on the Study Plan

Holt Geometry 3-1 Lines and Angles Hmwk 13.2 B: Practice: 18 – 25, 27, 29, 31, 33

Holt Geometry 3-1 Lines and Angles  Notes Notes Handout Unit Circle & Chart  Calculator

Holt Geometry 3-1 Lines and Angles cos 270º= sin 270º= (x, y) = (cos , sin  ) 0 C.

Holt Geometry 3-1 Lines and Angles cos 360º= sin 360º= (x, y) = (cos , sin  ) 1 0 D.

Holt Geometry 3-1 Lines and Angles cos 540º= sin 540º= (x, y) = (cos , sin  ) 0 E.

Holt Geometry 3-1 Lines and Angles 6. What are the cosine and sine of the angles? Use the unit circle handout.

Holt Geometry 3-1 Lines and Angles (x, y) = (cos , sin  ) A.  = 60º

Holt Geometry 3-1 Lines and Angles (x, y) = (cos , sin  ) A.  = 60º

Holt Geometry 3-1 Lines and Angles (x, y) = (cos , sin  ) A.  = 60º cos 60º= sin 60º=

Holt Geometry 3-1 Lines and Angles (x, y) = (cos , sin  ) B.  = 225º cos 225º= sin 225º=

Holt Geometry 3-1 Lines and Angles (x, y) = (cos , sin  ) C.  = -45º cos -45º= sin -45º= think: 315º

Holt Geometry 3-1 Lines and Angles (x, y) = (cos , sin  ) D.  = -270º cos -270º= sin -270º= think: 90º

Holt Geometry 3-1 Lines and Angles Summary Does a negative angle measure indicate negative values for sine and cosine?

Holt Geometry 3-1 Lines and Angles Hmwk 13.2 C: Math XL Work on the Study Plan