Stu: How do I find a midline on a graph, from an equation? it is 2y=acos (bx+c)+d
Hi Stu,
y = (a/2)cos[b(x+(c/b)] + d/2
midline y= d/2
amplitude = a/2
period = 2pi/b
phase shift = c/b to the left
I have plotted a graph to show you what is happening. The two graphs start the same. Move the sliders to show you what happens as the letters change in value.
I hope that you understand what I am trying to show you.
If I or someone else, can explain further, let us know.
https://www.desmos.com/calculator/gozti03ke3
Another source of information
http://math.ucsd.edu/~wgarner/math4c/textbook/chapter5/shift_trig_func.htm
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