The graph of a sinusoidal function has a maximum point at (0,10) and then intersects its midline at (4π,4).Write the formula of the function, where x is entered in radians.
Q. The graph of a sinusoidal function has a maximum point at (0,10) and then intersects its midline at (4π,4).Write the formula of the function, where x is entered in radians.
Determine Amplitude: Determine the amplitude A of the function.Since the maximum value is 10 and it intersects the midline at 4, the amplitude is the distance from the midline to the maximum value.A=10−4=6
Find Vertical Shift: Find the vertical shift D of the function.The midline value is 4, which is also the vertical shift.D=4
Determine Period: Determine the period T of the function.Since the function intersects the midline at 4π, and this is a quarter of the period away from the maximum, the full period is 4 times this value.T=4×(4π)=π
Calculate Value of B: Calculate the value of B in the function f(x)=Acos(Bx+C)+D, using the period T. The period T is related to B by the formula T=B2π. B=T2πB=π2πB=2
Determine Phase Shift: Determine the phase shift C of the function.Since the maximum point is at (0,10), there is no horizontal shift, and thus C=0.
Write Sinusoidal Function: Write the equation of the sinusoidal function using the values of A, B, C, and D. f(x)=Acos(Bx+C)+D f(x)=6cos(2x+0)+4 f(x)=6cos(2x)+4
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