Math Oct 3.notebook
October 03, 2013
Objective: Solve problems using the six trigonometric ratios for angles expressed in radians and degrees. Oct 2­4:57 PM
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Math Oct 3.notebook
October 03, 2013
Primary Trigonometric Ratios
Reciprocal Trigonometric Ratios
Oct 3­10:14 AM
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Math Oct 3.notebook
October 03, 2013
Recall: CAST
Oct 3­10:15 AM
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Math Oct 3.notebook
October 03, 2013
in degree mode
in radian mode
sin(30)
sin(π/6)
cos(135)
cos(3π/4)
You can determine approximate values for trigonometric ratios using technology, provided that your calculator is in the right mode! Oct 2­4:59 PM
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Math Oct 3.notebook
October 03, 2013
Oct 2­4:59 PM
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Math Oct 3.notebook
October 03, 2013
Oct 3­1:11 PM
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Math Oct 3.notebook
October 03, 2013
Reference Angles
For any given angle, its reference angle is an acute version of that angle. In standard position, the reference angle is the smallest angle between the terminal arm and the x­axis. The values of the trig functions of angle θ are the same as the trig values of the reference angle for θ, give or take a minus sign. Oct 3­10:17 AM
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Math Oct 3.notebook
October 03, 2013
Ex
Example
ExE
Point A (­12/13, 5/13) is on the unit circle and on the terminal arm of an angle θ in standard position. Determine the values for the six trigonometric ratios for angle θ. Oct 2­4:59 PM
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Math Oct 3.notebook
October 03, 2013
Key Ideas
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P(θ) = (cosθ, sinθ)
the reciprocal ratio of sine is cosecant
the reciprocal ratio of cosine is secant
the reciprocal ratio of tangent is cotangent
exact values of trig ratios for special angles and their multiples may be determined using the coordinates of points on the unit circle
• you can determine approximate values for trigonometric ratios using a calculator in the appropriate mode!!
Oct 2­5:18 PM
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Math Oct 3.notebook
October 03, 2013
Homework
pg 201­203 # 1­6 (odds), 8, 9, 13, 16, 17
Push Yourself! Try # 20 and 22! Oct 2­4:59 PM
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