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A sinusoidal function has an amplitude of 3.5 units, a period of 1080 degrees and a max at (0,4). What's is the equation?

User Mrry
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1 Answer

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Period = 1080 degrees = 1080 x pi / 180 = 6pi

Now, General eqn for wave = A sin(wt + C) + D

A = amplitude = 3.5
w = angular frequency
T = period = 6pi

w = 2pi / T = 2pi / 6pi = 1/3

So, our equation becomes = 3.5 sin(t / 3 + C) +D

max point is at (0, 4). Put it in the equation

so, y = 3.5 sin( t /3 + C) + D
where maximum value of y could be 4.

Maximum of 3.5 sin( t /3 + C) is 3.5.
Means D has to be 0.5 to make the maximum value of whole y to be 1

C could be any value. No information is given to find C.




User Simon Judd
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