Trigonometry L22Amplitudes and Periods

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Trigonometry L2-2 Amplitudes and Periods
Graphs of Sine and Cosine
y cosx
y sinx
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Definitions
The period of a trigonometric function is the
number of degrees taken before the graph repeats
itself.
The amplitude of a sinusoid is the distance from
its axis to a high point or low point.
The cycle of a periodic function is a portion of
the graph of the function from one point on the
graph to the point at which the graph starts to
repeat itself.
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Given y AsinB? or y AcosB?
A is the amplitude.
B is the number of times the sinusoid repeats in
360.
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Expectations for Sinusoidal Graphs
1. x and y-axes (zeros)
2. labeled center line value and dotted line
that represents it
3. labeled maximum and minimum values and dotted
line that represent them
4. labeled 5 critical numbers
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Ex. Graph the following
a) y 3sin?
amplitude 3
period 360
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b) y cos2?
amplitude 1
period 180
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amplitude 2
period 1440