1. Freq = 1 / [ 6pi]
The frequency is 1 / period....so the period is 6pi....
In the form y = Asin (Bx) + C
Amplitude = 2 = A
Midline .....y = 3 = C
To find B
B = 2pi/ period = 2pi / 6pi = 1/3
y -intercept = (0, 3)
The function is :
y = 2sin ( (1/3) x) + 3
Here's the graph : https://www.desmos.com/calculator/8hza0yorxy
2.
In the form Asin(Bx) + C
Amplitude = 2 = A
Midline y = 3 = C
To find B = 2pi/ period = 2pi / 4pi = 1/2
y intercept (0, 3)
The function is :
y = 2sin( (1/2) x ) + 3
Note that the parent function is :
y = -2sin ( (1/2) x ) - 3
Here's the graph of both : https://www.desmos.com/calculator/xnb8aumkek
3.
In the form y = Asin (Bx) + C
Period = 4 we need to find "B" thusly
B = 2pi / period = 2pi/ 4 = pi / 2
A is the amplitude = 4
C is the shift of the midline from y = 0.....thus.....the shift is 1 unit upward.....so C = 1
The function is
y = 4sin (pi * x / 2) + 1
Here's the graph :
4.
y = Asin(Bx + C )
A = the amplitude = [ difference in high/low/point ] / 2 = 6 / 2 = 3
The period is 20sec...so B =
2pi / period = 2pi / 20 = pi / 10
Since the sine graph starts at its highest position...the is a shift of pi/2 units to the left....thus C = pi/2
The function is :
y = 3sin ((pi/10) x + pi/2 )
The only question I have about this one is at the beginning of the observation, x = 0 and the weight will be at its highest point......thus.....the graph's first point will not be at the midline......that occurs 5 seconds later....
5.
We have this
y = Asin (Bx) + C
A is the amplitude = 5
The midline here is shifted down 8 units from normal.....thus C = -8
To find B we have
B = 2pi / period = 2pi / 16 = pi / 8
So the function is
y = 5 sin ( ( pi/ 8) x ) - 8
Here's the graph : https://www.desmos.com/calculator/vhovcnbzy3