Table of contents
- 0. Fundamental Concepts of Algebra3h 29m
- 1. Equations and Inequalities3h 27m
- 2. Graphs1h 43m
- 3. Functions & Graphs2h 17m
- 4. Polynomial Functions1h 54m
- 5. Rational Functions1h 23m
- 6. Exponential and Logarithmic Functions2h 28m
- 7. Measuring Angles40m
- 8. Trigonometric Functions on Right Triangles2h 5m
- 9. Unit Circle1h 19m
- 10. Graphing Trigonometric Functions1h 19m
- 11. Inverse Trigonometric Functions and Basic Trig Equations1h 41m
- 12. Trigonometric Identities 2h 34m
- 13. Non-Right Triangles1h 38m
- 14. Vectors2h 25m
- 15. Polar Equations2h 5m
- 16. Parametric Equations1h 6m
- 17. Graphing Complex Numbers1h 7m
- 18. Systems of Equations and Matrices3h 6m
- 19. Conic Sections2h 36m
- 20. Sequences, Series & Induction1h 15m
- 21. Combinatorics and Probability1h 45m
- 22. Limits & Continuity1h 49m
- 23. Intro to Derivatives & Area Under the Curve2h 9m
15. Polar Equations
Polar Coordinate System
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Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Plot the point on the polar coordinate system.
(−2,32π)
A
B
C
D

1
Understand that polar coordinates are given in the form (r, θ), where r is the radius (distance from the origin) and θ is the angle from the positive x-axis.
The given point is (-2, \(\frac{2\pi}{3}\)). The negative radius means we will plot the point in the opposite direction of the angle.
First, locate the angle \(\frac{2\pi}{3}\) on the polar coordinate system. This angle is in the second quadrant, 120 degrees counterclockwise from the positive x-axis.
Since the radius is negative, move 2 units in the opposite direction of \(\frac{2\pi}{3}\), which is equivalent to moving 2 units in the direction of \(\frac{5\pi}{3}\) (or 300 degrees).
Plot the point 2 units away from the origin in the direction of \(\frac{5\pi}{3}\). This is the correct location for the point (-2, \(\frac{2\pi}{3}\)).
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