Transcript File
1-11-16
T1.1d To Find Coterminal Angles
in Degrees and Radians
What do you call a midget psychic
on the run from the police?
A small medium at large!!
1
OPENER:
Convert to degrees:
8 180
5
8*180 / 5
288
Convert to π radians
(keep in rational form):
GCF? 60°
13
780
180
1
3
13
3
2
Active Learning Assignment Questions?
3
LESSON:
Angles are COTERMINAL if they share the same
initial and terminal sides, but with a different
number of rotations (forwards or backwards).
(A rotation is 360° for degrees and 2π for radians.)
4
Looking down at a merry go round, my nephew is
33° away from the ticket booth.
II
I
33°
Nephew
Ticket
booth
When it goes around the
III
first time, how many
degrees will he have gone
from the ticket booth?
33°
+360°
393°
IV
5
Example: Find two coterminal angles, one positive and
one negative, to the given angle.
178
Pos:
II
I
178°
+360°
0°
538°
Neg:
178°
-360°
III
IV
-182°
6
Try: Find two coterminal angles, one positive and one
negative, to the given angle.
1024.48
II
I
Pos: 1384.48° or
664.48° or
304.48°
Neg:
0°
-55.52°
III
IV
7
Try: Find two coterminal angles, one positive and one
negative, to the given angle.
582
II
I
-582°
Pos:
+360°
+360°
0°
138°
Neg:
-582°
-582°
– 360° or +360°
-942°
III
IV
-222°
8
Try: Find two coterminal angles, one positive and one
negative, to the given angle. If you are given a problem in π
radians the answer should be in π radians.
2
Remember this for the test!
3
2 2 3
3
1 3
2 6
3
3
8
3
Neg: 2
6
3
3
4
3
Pos:
II
I
0
2
III
IV
9
Try: Find two coterminal angles, one positive and one
negative, to the given angle.
2
7
Pos:
II
I
2 14
7
7
12
7
Neg:
2 14
7
7
16
7
0
III
IV
10
Active Learning Assignment:
P. 262: 17 (a-b), 18 (a-b), 19a, 21a
TEST ON THIS CHAPTER ON THURSDAY, 1/14
YOU WILL USE ONE OF MY CALCULATORS ON THE
TEST.
WE WILL HAVE A SMALL QUIZ ON DEFINITIONS ON
WEDNESDAY, 1/13. KNOW THESE DEFINITIONS:
Degree
Radian
Unit Circle
Coterminal Angle
Angle Initial Side
Angle Terminal Side
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