Find an equation for a sinusoidal function that has period 2Ο, amplitude 2, and contains the point (23Οβ,0). Write your answer in the form f(x)=Acos(Bx+C)+D, where A, B, C, and D are real numbers.
Q. Find an equation for a sinusoidal function that has period 2Ο, amplitude 2, and contains the point (23Οβ,0). Write your answer in the form f(x)=Acos(Bx+C)+D, where A, B, C, and D are real numbers.
Determine B Value: Determine the value of B using the given period of the function.Since the period of a cosine function is given by (2Ο)/B, we can set this equal to the given period of 2Ο and solve for B.Period: (2Ο)/B=2ΟB=(2Ο)/(2Ο)B=1
Set Amplitude and B: Since the amplitude is given as 2, we know that A=2. So far, we have:f(x)=2cos(Bx+C)+DSubstituting B=1, we get:f(x)=2cos(x+C)+D
Find C and D Values: Next, we need to determine the values of C and D. Since the function contains the point (3Ο/2,0), we can substitute x=3Ο/2 and f(x)=0 into the equation and solve for C and D.0=2cos(3Ο/2+C)+DSince cos(3Ο/2)=0, the equation simplifies to:0=2(0)+DD=0
Determine Phase Shift: Now we need to find the value of C. We know that the cosine function has a value of 0 at 23Οβ when it is at the mid-point between its maximum and minimum values. Since the amplitude is 2, the maximum and minimum values are 2 and β2, respectively. Therefore, the cosine function must be at 23Οβ for the first time at the mid-point of its period, which is Ο. This means that the phase shift C must be such that x+C=Ο when 00.010203
Substitute Values for Final Equation: Substitute the values of A, B, C, and D into the general form of the equation to get the final equation of the sinusoidal function.f(x)=2cos(xβ2Οβ)+0f(x)=2cos(x+2Οβ) (since cosine is an even function, cos(βΞΈ)=cos(ΞΈ))
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