The horizontal lines are at a height of "."
As "a" is increased, the amplitude (half the distance between high and low points) increases. (Negative values flip the graph vertically.)
The value of "b" affects the horizontal stretch and compression of the graph, and thus the period (the horizontal distance between peaks and the "time" it takes for the graph to repeat its periodic pattern).
As "b" increases the period shortens, as it decreases the period lengthens.
The value "" represents the phase shift and is the x-value for where the "first" period starts. An unshifted sine graph begins at "x=0," when "c=0."
The value "d" vertically shifts the graphs up and down the y-axis.

Use the sliders for a, b, c, and d to see the effect on the graph.

Calculate the Period, Amplitude and Phase Shift and then check you answers by clicking on the check boxes.

Created by Kathryn Brenneman for MA 111 at NC State University, Fall 2012
Modified from Dave Matthews "Amplitude of The Modified Sine Function"