Find an equation for a sinusoidal function that has period 4Ο, amplitude 2, and contains the point (2Ο,4). Write your answer in the form f(x)=Asin(Bx+C)+D, where A, B, C, and D are real numbers.
Q. Find an equation for a sinusoidal function that has period 4Ο, amplitude 2, and contains the point (2Ο,4). Write your answer in the form f(x)=Asin(Bx+C)+D, where A, B, C, and D are real numbers.
Determine B value: Determine the value of B using the period of the sinusoidal function.The period of a sinusoidal function in the form f(x)=Asin(Bx+C)+D is given by (2Ο)/B. Since the period is given as 4Ο, we can set up the equation:4Ο=(2Ο)/BSolving for B gives us:B=(2Ο)/(4Ο)B=1/2
Write general form: Write the general form of the sinusoidal function using the amplitude A and the value of B we just found.The amplitude is given as 2, so A=2. We have found B=21β. The general form of the function so far is:f(x)=2sin((21β)x+C)+D
Use given point: Use the given point (2Ο,4) to find the values of C and D. Plugging in the point (2Ο,4) into the equation gives us: 4=2sin(21β(2Ο)+C)+D Simplifying the sine term: 4=2sin(Ο+C)+D Since sin(Ο+C)=sin(Ο)cos(C)+cos(Ο)sin(C)=0β cos(C)β1β sin(C)=βsin(C), the equation becomes: 4=β2sin(C)+D
Determine C value: Determine the value of C using the properties of the sine function.Since the sine function oscillates between β1 and 1, and the coefficient of the sine function is β2, the only way for sin(C) to be 0 is for C to be an integer multiple of Ο. Therefore, we can choose C=0 (as one of the simplest solutions) without loss of generality.
Solve for D: Solve for D using the value of C we just determined.Substituting C=0 into the equation from Step 3:4=β2sin(0)+D4=0+DD=4
Write final equation: Write the final equation of the sinusoidal function using the values of A, B, C, and D we have found.Substituting A=2, B=21β, C=0, and D=4 into the general form:f(x)=2sin((21β)x+0)+4Simplifying the equation:f(x)=2sin((21β)x)+4
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