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Find an equation for a sinusoidal function that has period 2Ο€2\pi, amplitude 22, and contains the point (βˆ’Ο€2,βˆ’2)\left(-\frac{\pi}{2}, -2\right). 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 2Ο€2\pi, amplitude 22, and contains the point (βˆ’Ο€2,βˆ’2)\left(-\frac{\pi}{2}, -2\right). 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 based on the period.\newlineThe period of a sinusoidal function in the form f(x)=Asin⁑(Bx+C)+Df(x) = A\sin(Bx + C) + D is given by the formula Period=2Ο€B\text{Period} = \frac{2\pi}{B}. Since we are given that the period is 2Ο€2\pi, we can set up the equation and solve for B.\newlinePeriod=2Ο€B\text{Period} = \frac{2\pi}{B}\newline2Ο€=2Ο€B2\pi = \frac{2\pi}{B}\newlineB=1B = 1
  2. Write general form: Write the general form of the sinusoidal function with the amplitude and B value.\newlineSince the amplitude AA is given as 22, and we have found BB to be 11, the general form of the function so far is:\newlinef(x)=2sin⁑(x+C)+Df(x) = 2\sin(x + C) + D\newlineWe still need to find the values of CC and DD.
  3. Find phase shift and shift: Use the given point (βˆ’Ο€2,βˆ’2)(-\frac{\pi}{2}, -2) to find the phase shift CC and the vertical shift DD. Plugging the point into the equation, we get: βˆ’2=2sin⁑(βˆ’Ο€2+C)+D-2 = 2\sin(-\frac{\pi}{2} + C) + D Since sin⁑(βˆ’Ο€2)=βˆ’1\sin(-\frac{\pi}{2}) = -1, the equation becomes: βˆ’2=2(βˆ’1)+D-2 = 2(-1) + D βˆ’2=βˆ’2+D-2 = -2 + D D=0D = 0
  4. Find phase shift CC: Now that we have DD, we need to find CC, the phase shift.\newlineWe know that sin⁑(βˆ’Ο€/2)=βˆ’1\sin(-\pi/2) = -1, and we want the function to pass through the point (βˆ’Ο€/2,βˆ’2)(-\pi/2, -2). Since the amplitude is 22, the function must reach its minimum at this point. This means that the phase shift CC must be such that the argument of the sine function is βˆ’Ο€/2-\pi/2 when xx is βˆ’Ο€/2-\pi/2.\newlineSo we set up the equation:\newlineDD00\newlineSolving for CC gives us:\newlineDD22
  5. Write final equation: Write the final equation of the sinusoidal function using the values of AA, BB, CC, and DD. Substituting the values we found into the general form, we get: f(x)=2sin⁑(x+0)+0f(x) = 2\sin(x + 0) + 0 Simplifying, we have: f(x)=2sin⁑(x)f(x) = 2\sin(x)

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