Amplitude
Period
Translations
The graph of f(x)=sin x
Domain all Real numbers
Range -1 to 1
2
, 1
3
2
,
1
The graph of f(x)=sin x
Sin x is an odd function
3
2
, 1
2
, 1
2
,
1
3
2
,
1
Graph of f(x) = -sin x
Graph of the f(x) = Cos x
Domain: All real numbers
Range: -1 to 1
Graph of the f(x) = Cos x
Cos x is an even function
2
, 1
2
, 1
,
1
,
1
f ( x )
cos( x )
f ( x )
sin
2 x
The red graph is Sin and the blue is Cos
Amplitude changes the Range
Amplitude changes the Range
Since Amplitude is a distance, it is always positive.
To find it: the absolute value of the Maximum minus the Minimum divide by two.
Amp is written before the function y = a*sin x
Amplitude changes the Range
Max 7; Min - 1 Amp. 7
(
1 )
4
2
2
, 7
,
1
2
Period (wave length)
The distance before the function repeats its value. y = sin bx; here b is 1.
Period (wave length) y = sin 2x b = 2
2
period b
4
, 1
5
4
, 1
Translation to move the graph of the function y = sin (x + c): moves Right or Left
Here is y
sin
2
Translation to move the graph of the function y = sin x + d moves up or down
Here is y
sin x
2
With all the translations
The sine function is f(x) = d + a sin b(x +c)
The cosine function is f(x) = d + a cos b(x +c)
Applet for the Sine function
• http://www.analyzemath.com/trigonometry/ sine.htm
Homework
Page 307 – 310
#3, 9, 14, 20,
26, 32, 41, 49,
71, 78
Homework
Page 307 – 310
# 7, 12, 17, 23,
27, 36, 45, 60,
76, 86