Mustafa is staring at a pizza spinning on a wheel in a glass case.The pizza is cut into four even slices. The distance P(t) (in cm ) between the center of the tastiest looking slice and the door of the glass case as a function of time t (in seconds) can be modeled by a sinusoidal function of the form a⋅cos(b⋅t)+d.At t=0, the center of the tastiest looking slice is farthest from the door, at a distance of 30cm away. After 2π seconds, it is closest to the door, at a distance of 10cm.Find P(t).t should be in radians.P(t)=
Q. Mustafa is staring at a pizza spinning on a wheel in a glass case.The pizza is cut into four even slices. The distance P(t) (in cm ) between the center of the tastiest looking slice and the door of the glass case as a function of time t (in seconds) can be modeled by a sinusoidal function of the form a⋅cos(b⋅t)+d.At t=0, the center of the tastiest looking slice is farthest from the door, at a distance of 30cm away. After 2π seconds, it is closest to the door, at a distance of 10cm.Find P(t).t should be in radians.P(t)=
Given Information: We are given that the distance P(t) is modeled by a sinusoidal function of the form acos(bt)+d. At t=0, the distance is the maximum, which is 30cm. This means that the value of d plus a must equal 30cm, since the cosine function has its maximum value of 1 at t=0.
Maximum Distance: We also know that after 2π seconds, the distance is at its minimum, which is 10cm. This means that the value of d−a must equal 10cm, since the cosine function has its minimum value of −1 at t=2π for the first time.
Minimum Distance: From the two conditions, we can set up a system of equations:1. a+d=302. d−a=10Adding these two equations, we get 2d=40, which means d=20cm.
System of Equations: Subtracting the second equation from the first, we get 2a=20, which means a=10cm.
Solving for : Now we need to determine the value of . Since the pizza completes one full cycle from the farthest point to the closest point and back to the farthest point in seconds, the period of the function is 444\pi seconds. The period T of a cosine function is given by T = \frac{222\pi}{b}, so we have 444\pi = \frac{222\pi}{b}.
Solving for aaa: Solving for bbb, we get b=2π4π=12b = \frac{2\pi}{4\pi} = \frac{1}{2}b=4π2π=21.
Determining the Value of b: Now we have all the parameters for the sinusoidal function: a=10a = 10a=10 cm, b=12b = \frac{1}{2}b=21, and d=20d = 20d=20 cm. The function P(t)P(t)P(t) is therefore P(t)=10cos(12t)+20P(t) = 10\cos\left(\frac{1}{2}t\right) + 20P(t)=10cos(21t)+20.
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