# trigonometry

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2. Choose the point that lies on the curve r = 2 – 3 sin θ.

A. (-5, 3π/2)
B. (–2, π)
C. (1, π/2)
D. (5, π/2

3. Which of the following is not an approximate solution of x5 – 1 = 0?

A. 0.3090 – 0.9511i
B. 0.8090 + 0.5878i
C. 0.3090 + 0.9511i
D. –0.8090 + 0.5878i

5. Change -4√2 - 4√2i to trigonometric form.

A. 32 cis 135°
B. 8 cis 225°
C. 8 cis 45°
D. 32 cis 45°

6. Simplify (2 cis 100°)7.

A. 2 cis 700°
B. 128 cis 280°
C. 128 cis 340°
D. 2 cis 340°

8. Simplify 12(cos 52° + i sin 52°)/ 8(cos 128° + i sin 128°)

A. 3/2cis 152°
B. 3/2cis 76°
C. 3/2cis 180°
D. 3/2cis 284°

9. Simplify i 45.

A. –i
B. 1
C. i
D. –1

10. Given the rectangular-form point (–1, 4), which of the following is an approximate primary representation in polar form?

A. (4.12, 1.82)
B. −(4.12, 1.82)
C. (−4.12, −1.33)
D. (4.12, 4.96)

11. Simplify (√2 cis 47°)(3√8

A. 48 cis 223°
B. 12 cis 223°
C. 48 cis 136°
D. 12 cis 136°

12. Which of the following statements are true?
(i) r = 4 – 3 sin θ is the equation for a limaçon rotated 90°.

(ii) r = 3 cos 8θ is the equation for a rose curve with 8 petals.

(iii) rθ = 16 is the equation for a circle.

A. (ii) only
B. (i) only
C. (i) and (ii)
D. (i) and (iii)

13. Describe the rotation required to transform the graph of r = 4 − cos (θ − 30°) sin (θ − 30°) to the graph of r = 4 − cos θ sin θ.

A. 30° counterclockwise
B. 60° clockwise
C. 60° counterclockwise
D. 30° clockwise

14. Simplify (4 − 9i ) − (2 − 4i ).

A. 2 − 13i
B. 2 − 5i
C. −5 + 2i
D. 2 + 13i

15. Find the absolute value of –2 + 6i.

A. 4
B. 4√2
C. 2√2
D. 2√10