The graph of a sinusoidal function intersects its midline at (0,1) and then has a maximum point at (47π,5).Write the formula of the function, where x is entered in radians.f(x)=□
Q. The graph of a sinusoidal function intersects its midline at (0,1) and then has a maximum point at (47π,5).Write the formula of the function, where x is entered in radians.f(x)=□
Determine Amplitude: Determine the amplitude A of the sinusoidal function.The amplitude is the distance from the midline to the maximum point. Since the midline is at y=1 and the maximum point is at y=5, the amplitude A is 5−1=4.
Determine Vertical Shift: Determine the vertical shift D. The midline of the function is also the vertical shift D. Since the function intersects the midline at (0,1), D is 1.
Determine Period: Determine the period of the sinusoidal function.The period T is the distance between two consecutive maximum points. Since we only have one maximum point, we can use the fact that the maximum point occurs at (7π/4) and the function intersects the midline at (0,1). The next intersection with the midline after a maximum would be a quarter period away, so the period T is 4 times the x-coordinate of the maximum point, which is 4×(7π/4)=7π.
Determine Value of B: Determine the value of B.The value of B is related to the period by the formula B=T2π. Substituting the period T=7π, we get B=7π2π=72.
Determine Phase Shift: Determine the phase shift C. Since the function intersects its midline at (0,1), there is no horizontal shift, so C=0.
Write Sinusoidal Function: Write the equation of the sinusoidal function.We have found:A=4B=72C=0D=1Substitute these values into the general form of the sinusoidal function f(x)=Acos(Bx+C)+D.f(x)=4cos(72x+0)+1f(x)=4cos(72x)+1
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