1 / 16

10.3 Polar Coordinates

10.3 Polar Coordinates. One way to give someone directions is to tell them to go three blocks East and five blocks South. Another way to give directions is to point and say “Go a half mile in that direction.”.

devi
Download Presentation

10.3 Polar Coordinates

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 10.3 Polar Coordinates

  2. One way to give someone directions is to tell them to go three blocks East and five blocks South. Another way to give directions is to point and say “Go a half mile in that direction.” Polar graphing is like the second method of giving directions. Each point is determined by a distance and an angle. A polar coordinate pair determines the location of a point. Initial ray r – the directed distance from the origin to a point Ө – the directed angle from the initial ray (x-axis) to ray OP.

  3. Some curves are easier to describe with polar coordinates: (Circle centered at the origin) (Ex.: r = 2 is a circle of radius 2 centered around the origin) (Line through the origin) (Ex. Ө = π/3 is a line 60 degrees above the x-axis extending in both directions)

  4. More than one coordinate pair can refer to the same point. All of the polar coordinates of this point are: Each point can be coordinatized by an infinite number of polar ordered pairs.

  5. Tests for Symmetry: x-axis: If (r, q) is on the graph, so is (r, -q).

  6. Tests for Symmetry: y-axis: If (r, q) is on the graph, so is (r, p-q) or (-r, -q).

  7. Tests for Symmetry: origin: If (r, q) is on the graph, so is (-r, q) or (r, q+p) .

  8. Tests for Symmetry: If a graph has two symmetries, then it has all three:

  9. Try graphing this. (Pol mode)

  10. Circles: Lemniscates: Limaçons: r2 = a2sin(2θ) r = a cosθ r = a ± b(cosθ) r = a sinθ r2 = a2cos(2θ) r = a ± b(sinθ) SPECIAL GRAPHS Types of Limaçons: a > 0, b > 0 If , limaçon has an inner loop If , limaçon called a cardiod (heart shaped) If , limaçon with a dimple.

  11. Types of Limaçons: If , limaçon has an inner loop SPECIAL GRAPHS If , limaçon called a cardiod (heart shaped) If , limaçon with a dimple. If , convex limaçon.

  12. Rose curves: r = a cos(nθ) r = a sin(nθ) SPECIAL GRAPHS If n is odd, the rose will have n petals. If n is even, the rose will have 2n petals.

  13. CONVERTING TO RECTANGULAR COORDINATES: 1.) x = r cosΘ y = r sinΘ 2.)

  14. Example: Convert the point represented by the polar coordinates (2, π) to rectangular coordinates. x = r cos(θ) y = r sin(θ) So, (–2, 0) x = 2cos(π) y = 2 sin(π) x = –2 y = 0

  15. Example: Convert the point represented by the rectangularcoordinates (–1, 1) to polarcoordinates.

  16. Converting Polar Equations • You can convert polar equations to parametric equations using the rectangular conversions. • Example:

More Related