Expert: Bobby Soltani - 4/12/2005

Question
Determine the amplitude and period of each function. Then graph one period of the function.
(1)y=sin 4 x
(2)y=2 sin 1/4 x
(3)y=3 sin 2 pi x
(4)y=-2 sin pi x
(5)y=-sin 4/3 x

Determine the amplitude, period and phase shift of each function. Then graph one period of the function.
(6)y=sin (x - pi/2)
(7)y=sin (2x - pi/2)
(8)y=3 sin (2x - pi/2)
(9)y=1/2 sin (x + pi)
(10)y=-3 sin (2x + pi/2)
(11)y=3 sin (2pi x + 4)
(12)y=-3 sin (2pi x + 4pi)  

Answer
Hi Casy,

It is difficult for me to help you with the graphing part of these questions since I only have this text box to work with.  Here are the formulas for finding amplitude, period, and phase shift.

y = a*sin(bx + c)

period = 2*pi/ABS(b)
where ABS(b) is the absolute value of b

amplitude = ABS(a)

phase shift = -c/b
a positive phase shift means that the sin is shifted to the right -c/b units.

Let me know if you have any specific questions.  Good luck.

Bobby