Summary of Trig functions grade 11 and 12: Horizontal shift
Main Ideas and Concepts
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Horizontal Shifting of Trigonometric Graphs:
The video focuses on how trigonometric graphs can shift horizontally, specifically using the sine function as an example. Horizontal shifting is different from vertical shifting and stretching.
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Graphing Process:
The speaker demonstrates how to graph the function \( \sin(x) - 30 \) over the interval of 0 to 360 degrees using a calculator. Important steps in using the calculator include:
- Setting the mode to table.
- Inputting the equation.
- Defining the start (0) and end (360) points.
- Setting the step size to \( \frac{\text{Period}}{4} \) (for a sine graph, the period is 360, so the step is 90).
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Plotting Points:
The speaker plots key points based on calculator outputs and adjusts for the horizontal shift caused by the \(-30\) in the equation. Important points include:
- At \( x = 0 \), \( y \approx -0.5 \)
- At \( x = 90 \), \( y \approx 0.866 \)
- At \( x = 180 \), \( y \approx -0.5 \)
- At \( x = 270 \), \( y \approx -0.866 \)
- At \( x = 360 \), \( y \approx -0.5 \)
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Amplitude, Range, Domain, and Period:
- Amplitude: The maximum distance from the resting position, which is 1 for the sine function.
- Range: The set of y-values, which is from -1 to 1.
- Domain: The set of x-values, which is from 0 to 360 degrees.
- Period: The time it takes for the graph to repeat, which remains 360 degrees for this function since it is only shifted, not stretched or compressed.
Methodology / Instructions
- Graphing a sine function with Horizontal Shift:
- Set the calculator to table mode.
- Input the equation \( \sin(x) - 30 \).
- Define the start point (0) and the end point (360).
- Calculate the step size as \( \frac{360}{4} = 90 \).
- Plot the points derived from the calculator outputs.
- Adjust the plotted points based on the horizontal shift (e.g., \( -30 \) shifts points to the right).
- Analyze and label the Amplitude, Range, Domain, and period of the graph.
Speakers/Sources Featured
- The speaker in the video is not named, but they are presumably an educator or tutor explaining the concept of horizontal shifting in trigonometric functions.
Notable Quotes
— 00:00 — « No notable quotes »
Category
Educational