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Find an equation for a sinusoidal function that has period 4Ο€4\pi, amplitude 22, and contains the point (2Ο€,4)(2\pi,4). Write your answer in the form f(x)=Asin⁑(Bx+C)+Df(x)=A\sin(Bx+C)+D, where AA, BB, CC, and DD are real numbers.

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Q. Find an equation for a sinusoidal function that has period 4Ο€4\pi, amplitude 22, and contains the point (2Ο€,4)(2\pi,4). Write your answer in the form f(x)=Asin⁑(Bx+C)+Df(x)=A\sin(Bx+C)+D, where AA, BB, CC, and DD are real numbers.
  1. Determine B value: Determine the value of B using the period of the sinusoidal function.\newlineThe period of a sinusoidal function in the form f(x)=Asin⁑(Bx+C)+Df(x) = A\sin(Bx + C) + D is given by (2Ο€)/B(2\pi)/B. Since the period is given as 4Ο€4\pi, we can set up the equation:\newline4Ο€=(2Ο€)/B4\pi = (2\pi)/B\newlineSolving for B gives us:\newlineB=(2Ο€)/(4Ο€)B = (2\pi)/(4\pi)\newlineB=1/2B = 1/2
  2. Write general form: Write the general form of the sinusoidal function using the amplitude AA and the value of BB we just found.\newlineThe amplitude is given as 22, so A=2A = 2. We have found B=12B = \frac{1}{2}. The general form of the function so far is:\newlinef(x)=2sin⁑((12)x+C)+Df(x) = 2\sin(\left(\frac{1}{2}\right)x + C) + D
  3. Use given point: Use the given point (2Ο€,4)(2\pi, 4) to find the values of CC and DD. Plugging in the point (2Ο€,4)(2\pi, 4) into the equation gives us: 4=2sin⁑(12(2Ο€)+C)+D4 = 2\sin\left(\frac{1}{2}(2\pi) + C\right) + D Simplifying the sine term: 4=2sin⁑(Ο€+C)+D4 = 2\sin(\pi + C) + D Since sin⁑(Ο€+C)=sin⁑(Ο€)cos⁑(C)+cos⁑(Ο€)sin⁑(C)=0β‹…cos⁑(C)βˆ’1β‹…sin⁑(C)=βˆ’sin⁑(C)\sin(\pi + C) = \sin(\pi)\cos(C) + \cos(\pi)\sin(C) = 0\cdot\cos(C) - 1\cdot\sin(C) = -\sin(C), the equation becomes: 4=βˆ’2sin⁑(C)+D4 = -2\sin(C) + D
  4. Determine CC value: Determine the value of CC using the properties of the sine function.\newlineSince the sine function oscillates between βˆ’1-1 and 11, and the coefficient of the sine function is βˆ’2-2, the only way for sin⁑(C)\sin(C) to be 00 is for CC to be an integer multiple of Ο€\pi. Therefore, we can choose C=0C = 0 (as one of the simplest solutions) without loss of generality.
  5. Solve for D: Solve for D using the value of CC we just determined.\newlineSubstituting C=0C = 0 into the equation from Step 33:\newline4=βˆ’2sin⁑(0)+D4 = -2\sin(0) + D\newline4=0+D4 = 0 + D\newlineD=4D = 4
  6. Write final equation: Write the final equation of the sinusoidal function using the values of AA, BB, CC, and DD we have found.\newlineSubstituting A=2A = 2, B=12B = \frac{1}{2}, C=0C = 0, and D=4D = 4 into the general form:\newlinef(x)=2sin⁑((12)x+0)+4f(x) = 2\sin(\left(\frac{1}{2}\right)x + 0) + 4\newlineSimplifying the equation:\newlinef(x)=2sin⁑((12)x)+4f(x) = 2\sin(\left(\frac{1}{2}\right)x) + 4

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