Determine an equation using a transformation of y =sinx that models depth in this bay
- Thread starter Bilal7
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Where does the first cycle begin? Where does that first cycle end? This is the period.
What is the least height? What is the greatest height? What is the difference between the greatest and least values? What is half of this difference? This is the amplitude.
What height is midway between the least and greatest heights? This is the center-line of the graph. How high is this above the x-axis? This is the vertical shift.
...and so forth. If you get stuck, please reply showing your work and reasoning, starting with your answers to the above questions. Thank you!
Where does the first cycle begin? Where does that first cycle end? This is the period.
What is the least height? What is the greatest height? What is the difference between the greatest and least values? What is half of this difference? This is the amplitude.
What height is midway between the least and greatest heights? This is the center-line of the graph. How high is this above the x-axis? This is the vertical shift.
...and so forth. If you get stuck, please reply showing your work and reasoning, starting with your answers to the above questions. Thank you!
So the period would be 12, 18 would be the amplitude and the midway height would be 20. Since the graph start 4 units above the x-axis, that would be the translation? So where do I plug in these values in order to create the equation? Thanks.
- Joined
- Feb 4, 2004
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Yes. The first period begins at "0" and ends at "12", so the period is 12 - 0 = 12 units.
How did you obtain this value?
Yes; the max is 36, the min is 4, so the "average" height is y = (36 + 4)/2 = 40/2 = 20.
No. Try using the steps and thinking listed earlier. In this case, where is the usual center line of a sine wave? Where is the center line of this sine wave? So what then must be the vertical shift?
What generic-form equation have they given you for trig functions and graphing? (Also, what have you noticed, based on the graphing you've studied and done yourself?)
Thank you!
D
Deleted member 4993
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According to your graph - at x = 0, y = ?
According to your equation - at x = 0, y = ?
Are those equal?
In the graph, the y value is 4 when x is 0, but in my equation it is 20. Oops, where did I go wrong? :?
Should the c value be 4 then?
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D
Deleted member 4993
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You have to shift x-axis now to match the given graph.
You mean the k value?
D
Deleted member 4993
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I don't know what does 'k' stand for!!
You have not shared the equation you are trying to use.
That would be y = asin(k(x-d)) + c