The Polar Coordinate System is a coordinate plane

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The Polar Coordinate System is a coordinate plane based on the dimensions r and

The Polar Coordinate System is a coordinate plane based on the dimensions r and q.

Points on a Polar Graph l A point on a polar coordinate plane is

Points on a Polar Graph l A point on a polar coordinate plane is given by the ordered pair, (r, q), where: l r = distance from origin to point q = angle in standard position to the point l

The Polar Grid

The Polar Grid

Plotting a Point

Plotting a Point

More Than One Ordered Pair Can Describe a Point

More Than One Ordered Pair Can Describe a Point

Negative ‘r’ Values

Negative ‘r’ Values

Name 4 Ordered Pairs

Name 4 Ordered Pairs

#1: Counter-Clockwise

#1: Counter-Clockwise

#2: Clockwise (negative q)

#2: Clockwise (negative q)

#3: CCW/flipped (neg. r)

#3: CCW/flipped (neg. r)

#3: CW/flipped (neg. q & neg. r)

#3: CW/flipped (neg. q & neg. r)

Name 4 Ordered Pairs

Name 4 Ordered Pairs

Try these l Plot (3, 120°) l Plot (- 5, 210°) l Plot (4

Try these l Plot (3, 120°) l Plot (- 5, 210°) l Plot (4 , - 90°) l Plot (- 2 , -165°)

Try these three other ordered pairs for the point (5, - 100°). l Name

Try these three other ordered pairs for the point (5, - 100°). l Name three other ordered pairs for the point (1, 200°). l Name

Basic Polar Graphs l l We graph Equations in the Polar Coordinate System that

Basic Polar Graphs l l We graph Equations in the Polar Coordinate System that are in terms of r and q. We will consider the following: • r=k • q=k (r = a constant) (q = a constant)

Graph r = k The coordinate, r, tells us how far from the origin

Graph r = k The coordinate, r, tells us how far from the origin to put a point. The equation r = 4 stands for : ‘all the points that are 4 units from the origin’. What would the graph of all these points look like?

r = 4 is a CIRCLE

r = 4 is a CIRCLE

Graph q = k The coordinate, q, tells us along what angle a point

Graph q = k The coordinate, q, tells us along what angle a point lies. The equation q = 120° stands for : ‘all the points that are along the 120° line’. What would the graph of all these points look like?

q = 120° is a LINE Notice the line is in both quadrants 2

q = 120° is a LINE Notice the line is in both quadrants 2 & 4. The points in quadrant 4 are points with q = 120° and a NEGATIVE value for r.

Summary l l Points in a Polar Grid are given by (r, q) -

Summary l l Points in a Polar Grid are given by (r, q) - the values of r and q can be positive or negative. Each point can be given by several different ordered pairs. The polar equation r = k is a circle. The polar equation q = k is a line.