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Ch. 1 - Functions
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Not the one you use?Change textbook
Chapter 1, Problem 98

Identify the amplitude and period of the following functions.
p(t)=2.5sin(12(t3))p\(\left\)(t\(\right\))=2.5\(\sin\]\left\)(\(\frac\)12\(\left\)(t-3\(\right\))\(\right\))

Verified step by step guidance
1
First, let's identify the function type. The function p(t) = 2.5sin(1/2(t-3)) is a sine function, which is generally expressed in the form A*sin(B(t - C)) + D, where A is the amplitude, B affects the period, C is the horizontal shift, and D is the vertical shift.
The amplitude of a sine function is the coefficient in front of the sine term. In this case, the amplitude is 2.5, which means the maximum value of the function is 2.5 units above and below the midline of the function.
Next, let's determine the period of the function. The period of a sine function is given by the formula 2π/B, where B is the coefficient of t inside the sine function. Here, B is 1/2.
To find the period, substitute B = 1/2 into the formula for the period: 2π/(1/2). This calculation will give you the period of the function.
Finally, note that the function has a horizontal shift due to the (t-3) term. This shift does not affect the amplitude or period but indicates the function is shifted 3 units to the right on the t-axis.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Amplitude

Amplitude refers to the maximum value of a periodic function, specifically the height of the wave from its midline to its peak. In the function p(t) = 2.5sin(1/2(t-3)), the amplitude is represented by the coefficient of the sine function, which is 2.5. This means the function oscillates between 2.5 and -2.5.
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Period

The period of a periodic function is the length of one complete cycle of the wave. For the sine function, the standard period is 2π. In the given function, the period can be calculated by taking the coefficient of t inside the sine function, which is 1/2. The period is then found using the formula: Period = 2π / (1/2) = 4π.
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Phase Shift

Phase shift refers to the horizontal shift of a periodic function along the x-axis. In the function p(t) = 2.5sin(1/2(t-3)), the term (t-3) indicates a phase shift of 3 units to the right. This means the entire wave is shifted rightward, affecting the starting point of the sine wave but not its amplitude or period.
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