Angle or Coordinate?
Students often get angles and coordinates mixed up after the concept of inverse trig functions is introduced. Hopefully thinking about the following will help you avoid that confusion.
Suppose
- cos a = b
- sin -1c = d
- cos(cos -1f) = g
- sin -1(sin h) = k
Assume all of the expressions are defined for the values given, i.e. a, c, f, and h are in the domains of their respective functions.
- For each of the following determine whether the object named is an angle or a coordinate on the unit circle.
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a |
b |
c |
d |
f |
g |
h |
k |
| Angle |
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| Coordinate |
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- Which one of the following statements must be true?
Solutions