Handout for Section 10.2
Math 101B
On your graphing calculator, go to MODE and
1. choose Radian (not Degree)
and 2. choose Pol or Polar (in the line that starts with Func or Function)
In the Graph menu, you'll now have "r = " instead of "y =".
Also, in the Range or Window, you'll now have "θmin", "θmax", and "θstep" in
addition to the xmin, xmax, and so on.
Set θmin = 0, θmax = 2π, and θstep = π /90.
Ex 9. Set xmin = –3, xmax = 3, xscl = 1, ymin = –2, ymax = 2, yscl = 1. Enter
each of the following functions, and sketch its graph.
a) r = 1 – cos θ
b) r = 1 – sin θ
y
y
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€
x
x
c) r = 1 + cos θ
d) r = 1 + sin θ
y
y
€
€
x
x
1
Ex 10. Set xmin = –25, xmax = 5, xscl = 5, ymin = –10, ymax = 10, yscl = 5.
Enter each of the following functions, and sketch its graph.
a) r = 6 – 9 cos θ
b) r = 6 – 6 cos θ
y
y
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€
x
x
c) r = 6 – 5 cos θ
d) r = 6 – 3cos θ
y
y
€
€
x
x
Ex 11. Set xmin = –3, xmax = 3, xscl = 1, ymin = –2, ymax = 2, yscl = 1. Solve for
r and enter the function, and then sketch its graph.
a) r 2 = 4 sin 2θ
b) r 2 = 4 cos 2θ
y
y
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€
x
x
2
Handout for Section 10.2
Math 101B
Ex 12. Set xmin = –3, xmax = 3, xscl = 1, ymin = –2, ymax = 2, yscl = 1.
Enter each of the following functions, and sketch its graph.
a) r = 2 sin (5θ )
b) r = 2 sin ( 7θ )
y
y
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€
x
x
c) r = 2 sin (6θ )
y
€
x
3
Preview of Section 10.4
Set xmin = –5, xmax = 25, xscl = 5, ymin = –10, ymax = 10, yscl = 5.
Enter each of the following functions, and sketch its graph.
4
1 – 0.8 cos θ
a) r =
6
1 + 1.5 cos θ
b) r =
y
y
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€
x
c) r =
x
4
1 – cos θ
y
€
x
4