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Trigonometry
The science of studying angle measure
Angle: two rays with
same initial point
The measure of an angle
is the amount of rotation
required to rotate one side,
called the initial side, to the
other side, called the
terminal side.
An angle at standard
position: if its vertex is at the
origin of the rectangular
coordinate system and its initial
side lies along the positive xaxis
Negative: since
the angle rotated
clockwise
Positive: since
the angle rotated
counterclockwise
Degree Measure
A Circle can be divided into 3600
Radian Measure
∏
2
∏
2∏
3∏
2
Examples:
Convert degree to radian measure
Convert the following Radian Measure to Degree
2∏ =1200
3
5∏ =1500
6
∏
6
=300
5∏ =3000
3
Convert the following Degree to Radian Measure
2100
7∏
6
1350
3∏
4
600
∏
3
2250
5∏
4