Which transformations are needed to change the parent cosine function to the cosine function below?
2 answers:
Question:
1. vertical stretch of 2, horizontal stretch to a period of 2 pi, phase shift of StartFraction pi Over 2 EndFraction units to the right, vertical shift of 1 unit up
2. vertical compression of 2, horizontal stretch to a period of StartFraction pi Over 4 EndFraction, phase shift of StartFraction pi Over 4 EndFraction units to the left, vertical shift of 2 units down
3. vertical compression of 2, horizontal compression to a period of 4 pi, phase shift of StartFraction pi Over 3 EndFraction units to the left, vertical shift of 1 unit down
4. vertical stretch of 2, horizontal compression to a period of StartFraction pi Over 2 EndFraction, phase shift of Pi units to the right, vertical shift of 1 unit down
Answer:
The correct option is;
4. Vertical stretch of 2, horizontal compression to a period of π/2, phase shift of π units to the right, vertical shift of 1 unit down
Step-by-step explanation:
Here, we have the parent cosine function given by y = cos(x)
A plot of the above function is attached
By comparison, it is observed that the transformation required to change the parent function includes;
1. Vertical stretch from the parent function of amplitude 1 to amplitude 2
2. A horizontal compression so that the period of one complete revolution is π/2 rather than 2·π in the parent cosine function
3. Phase shift of pi units to the right such that cos(π) = 1 rather than cos(2π) = 1 as it applies to the parent function
4. Shift of the y values from the symmetrical x-axis origin downwards by 1 unit such that the maximum y value of the doubly stretched transformation is 1 rather than 2
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