Review
Unit circle - sine, cosine
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1
Question 1
Convert 30° into radians.
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Question 1 - Answer
Topic:
Degrees - radians
30° are π/6 radians
3
Question 2
Convert 4π/3 radians into degrees.
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Question 2 - Answer
Topic:
Degrees - radians
4π/3 radians are 240°
5
Question 3
In the unit circle, sine is the projection of the radius to:
a) the x-axis
b) the y-axis
b) the origin
d) line x = 1
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Topic:
Unit circle - sine
Question 3 - Answer
In the unit circle, sine is the projection of the radius to:
a) the x-axis
b) the y-axis 
b) the origin
d) line x = 1
7
Question 4
What is the value of sin60° ?
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Question 4 - Answer
Topic:
Unit circle - sine
sin60° = √3/2
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Question 5
In the unit circle, cosine is the projection of the radius to:
a) the x-axis
b) the y-axis
b) the origin
d) line x = 1
10
Question 5 - Answer
In the unit circle, cosine is the projection of the radius to:
a) the x-axis 
b) the y-axis
b) the origin
d) line x = 1
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Question 6
What is the value of cos45° ?
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Question 6 - Answer
cos45° = 1/√2 or √2/2
13
Question 7
.What is the value of sin(-60°) ?
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Question 7 - Answer
Topic:
Opposite angles
sin(-60°) = sin(360°- 60°) = sin300° = -√3/2
15
Question 8
.What is the value of sin120° ?
16
Question 8 - Answer
Topic:
Supplementary
angles
sin120° = sin(180° - 60°) = sin60° = √3/2
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Question 9
What is the value of cos135° ?
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Question 9 - Answer
Topic:
Supplementary
angles
cos135° = cos(180° - 45°) = - cos45° = -1/√2 or -√2/2
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Question 10
. Is cos30° = sin60° ?
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Question 10 - Answer
Topic:
Complementary
angles
Yes, since 30° + 60° = 90° (complementary angles)
and cos30° = sin60°
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Question 11
. How many degrees is 1 radian?
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Question 11 - Answer
Topic:
Degrees - radians
. How many degrees is 1 radian?
π/1 = 180°/x ⇒ x = 180°/π = 57.3°
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