Let's delve into the periodic phenomena and the analysis of the given functions \( f(x) \) and \( g(x) \) in detail.
Real-World Examples of Periodic Phenomena:
- Seasons: Due to Earth's axial tilt and orbit, we experience a repeating cycle of seasons.
- Tides: Regular fluctuations in ocean water levels caused by the gravitational forces of the Moon and Sun, occurring approximately every 12.5 hours.
- Day and Night: The Earth's rotation leads to a predictable cycle of light and darkness every 24 hours.
- Heartbeats: The heart's rhythmic contractions produce a consistent pattern that can vary with activity, stress, and health.
- Sound Waves: Sound is created by vibrations in a medium, displaying periodic characteristics defined by frequency and wavelength.
- Pendulum Motion: A classic example of periodic motion, where a pendulum swings back and forth in a regular and predictable manner.
Analysis of Functions
Function \( f(x) = 2\sin(3x) + 5 \)
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Amplitude: The amplitude is given by the coefficient of the sine function, which is 2. This means the maximum displacement from the midline is 2 units.
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Midline: The midline of the graph is shifted vertically due to the constant term added to the sine function. Here, the midline is set at \( y = 5 \).
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Period: The period of a sine function can be calculated using the formula: \[ \text{Period} = \frac{2\pi}{b} \] where \( b \) is the coefficient of \( x \). For \( f(x) \), \( b = 3 \): \[ \text{Period} = \frac{2\pi}{3} \]
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Phase Shift: There is no horizontal shift or phase shift in this function since there are no added or subtracted terms involving \( x \).
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Graph Behavior: The function oscillates above and below the midline: \[ \text{Minimum} = 5 - 2 = 3, \quad \text{Maximum} = 5 + 2 = 7 \] Thus, \( f(x) \) oscillates between 3 and 7.
Function \( g(x) = 5 \cos(\pi x) - 2 \)
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Amplitude: The amplitude is 5, indicating that the graph will oscillate 5 units above and below the midline.
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Midline: The midline here is at \( y = -2 \).
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Period: For the cosine function, the formula is the same: \[ \text{Period} = \frac{2\pi}{b} \] Here, we find \( b \): \[ g(x) = 5\cos(\pi x) \Rightarrow b = \pi \quad \Rightarrow \quad \text{Period} = \frac{2\pi}{\pi} = 2 \]
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Graph Behavior: This cosine function oscillates around the midline: \[ \text{Minimum} = -2 - 5 = -7, \quad \text{Maximum} = -2 + 5 = 3 \] Thus, \( g(x) \) oscillates between -7 and 3.
Summary
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Function \( f(x) \):
- Amplitude: 2
- Midline: y = 5
- Period: \( \frac{2\pi}{3} \)
- Range: [3, 7]
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Function \( g(x) \):
- Amplitude: 5
- Midline: y = -2
- Period: 2
- Range: [-7, 3]
Both functions share periodic characteristics, highlighting the beauty of periodicity in mathematics and nature.