PC 4.4 Notes

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10/12-13/2010

4.4: Trigonometric Functions of Any AngleFind the sine, cosine, and tangent of the following angles and determine what quadrant they terminate in.

Angle Quadrant sin cos tan

130° II 0.766 –0.643 –1.192

290° IV –0.940 0.342 –2.747

5π/4 III –0.707 –0.707 1

2π/9 I 0.643 0.766 0.839

PC 4.4 Notes

Fjelstrom

10/12-13/2010

PC 4.4 Notes

Fjelstrom

10/12-13/2010

Remember that…

All Students Take Calculus

PC 4.4 Notes

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10/12-13/2010

Ex. 1) (–2, 3) is a point on the terminal side of ϴ. Find the six trigonometric functions for ϴ.

PC 4.4 Notes

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10/12-13/2010

Ex. 2) sin ϴ = 4/5 and tan ϴ < 0. Find cos ϴ.

PC 4.4 Notes

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10/12-13/2010

Ex. 3) tan ϴ = 5/6 and sin ϴ < 0. Find sec ϴ.

PC 4.4 Notes

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10/12-13/2010

The one-handed trick…When evaluating trig functions:Step 1) Find the trig function for the reference angleStep 2) Determine the sign (+ or -) for the value based on the terminating quadrant.

More info at http://function-of-time.blogspot.com/2009/08/trig-reference-angle-cheat-hand.html

PC 4.4 Notes

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10/12-13/2010

Ex. 5) Evaluate without a calculator. (BM 10)

PC 4.4 Notes

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Going Backwards…

Ex. 6) Find the value(s) for ϴ that make the statement true. (BM 11)

PC 4.4 Notes

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10/12-13/2010

Assignment:

#16 p. 318 #1, 5, 7, 11, 14, 17-23 (odd), 29-57 (odd), 61, 62, 81-85 (odd)

PC 4.4 Notes

Fjelstrom

10/12-13/2010

PC 4.4 Notes

Fjelstrom

10/12-13/2010