Why is amplitude negative

In other words, our graphs are the same as when a was a positive value, but are now reflected across the x-axis. To see a direct comparison between positive and negative values of a , click here. Watch the animation of our sine curve as a goes from -5 to 5. Notice how different values of a change the amplitude of our sine curve.

See how the curve appears to be growing in height in the y direction. Let's begin by exploring positive values of b.

What happens to the corresponding graphs as the value of b changes? This time, different values of our coefficient result in different points of intersection at the x-axis. By choosing different positive values of the coefficient b , we can see our original sine curve has changed only in period , or the length of one cycle. In other words, the period for the sine curve to make one full osscilation is no longer from 0 to 2pi.

What happens when b has a negative value? Again, the period of the original sine curve has changed here, as we would expect.

The difference with a negative value of b however, is our sine curves have the same period as the positive values of b above, but now they are reflected across the x-axis. For a direct comparison between positive and negative values of b , click here. Watch the animation of our sine curve as b goes from -5 to 5. Notice how different values of b change the period of our sine curve.

See how the curve appears to be contracting and expanding along the x-axis. First, let's look at the graphs generated for positive values of c. Amplitude is positive as far as I know. Think of it this way, it is the distance of the maximum and minimum from the Centre axis. Let me know if you need further help or suggestions. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Create a free Team What is Teams? Learn more. Do you ever say that the amplitude is negative? Ask Question. Asked 7 years, 5 months ago. Active 7 years, 5 months ago. Viewed 32k times. The proper definition is to take half the difference of the maximum value minus the minimum value, which will produce a positive value as also discussed in answers below. Add a comment.

Active Oldest Votes. I can't think of many cases where it is useful to make a distinction between these identical functions. Sign up or log in Sign up using Google. Sign up using Facebook.