Answer: 6pi radians
(this is equivalent to 1080 degrees)
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Step-by-step explanation:
f(x) = sin(x/3)
is the same as
f(x) = 1*sin( (1/3)(x-0) )+0
and that is in the form
f(x) = A*sin( B(x-C) )+D
The letters A,B,C,D are explained below
A = helps find the amplitude
B = 2pi/T, where T is the period
C = determines phase shift (aka left/right shifting)
D = determines vertical shift = midline
All we care about is the value of B as that is the only thing that is connected to the period T
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Compare f(x) = 1*sin( (1/3)(x-0) )+0 with f(x) = A*sin( B(x-C) )+D and we see that B = 1/3, so,
B = 2pi/T
1/3 = 2pi/T
1*T = 3*2pi ... cross multiply
T = 6pi
The period is 6pi radians. This is equivalent to 1080 degrees. To convert from radians to degrees, you multiply by (180/pi).