SOLUTION: The graph of cos(T) is shifted left 270°, has the period decreased to 180°, and is shifted up 2 units. What is the transformed equation?

Algebra.Com
Question 1143426: The graph of cos(T) is shifted left 270°, has the period decreased to 180°, and is shifted up 2 units. What is the transformed equation?
Found 2 solutions by KMST, greenestamps:
Answer by KMST(5328)   (Show Source): You can put this solution on YOUR website!
The graph of (with in degrees) has a period of .
In every period there is a single maximum value of , such as at .
goes through a maximum at , and as increases,
it has the next maximum at .
After that, the next maximum is at , and so on.
Here is a piece of the graph of with in degrees:
,

We want to do 3 changes to get to the "transformed equation", and there often is more than one way to get to a destination, but some ways may be "smoother sailing" compared to others.

CHANGES IN THE ORDER LISTED:
If we want shift the graph to the left, we would end with a maximum at .
A way textbooks suggest to do that shift is replacing the variable with another, such as replacing .
hat way the point for is at .
We would have .
The graph of as a function of is shown below.


If after that we want to change the period to ,
we can do that by changing to variable , so that it increases twice as fast as .
If we still want the maximum at , we need to make ,
and change the function from to . The graph of as a function of is shown below.


Finally, to shift an x-y graph up by two units, we just add to the expression for .
The graph of as a function of is shown below.



A DIFFERENT WAY:
With , we change the function from to ,
and that changes the period from to .
The graph of as a function of is shown below.

To shift the graph to the left we change to to get
Finally, we add to shift the graph up by units, and get .

NOTE: There are other expressions with the same graph, such as :
.

Answer by greenestamps(13200)   (Show Source): You can put this solution on YOUR website!


With the amplitude unchanged, the general equation is



where c is the horizontal (phase) shift and d is the vertical shift. b is the normal period of 360 degrees, divided by the actual period.

(1) The basic graph:

(2) Shifted 270 degrees left --> c = -270:

(3) Period changed from 360 degrees to 180 degrees --> b = 360/180=2: or

(4) Shifted up 2 --> d = 2:

RELATED QUESTIONS

Describe the graph of y=(x+5)^2 - 8. What graph is it. The correct answer is one of... (answered by MathLover1)
How does the graph of g(x) = (x-4)² + 3 compare to the parent function f(x) = x²? A.... (answered by math_tutor2020,josgarithmetic)
The graph of tan(T) is shifted right 45° and has the period increased to 540°. What is... (answered by Theo)
The graph of tan(T) is shifted right 90° and has the period increased to 360°. What is... (answered by Edwin McCravy)
The parent function is f(x)=2^x-^1+3 and the new function is g(x)=2^x+^2+5 How does the... (answered by ikleyn)
Consider {{{g(x) = (x + 2)^3 + 2}}}; what is the new equation for {{{g(x)}}} if it is... (answered by Edwin McCravy)
Please help me write this equation : Write an equation in vertex form whose graph is... (answered by ikleyn)
9. Write an equation that defines the graph of y = x2 after it is shifted vertically 2... (answered by MathLover1,josmiceli)
The graph of f(x) = x^2 is reflected in the x axis, vertically stretched by a factor of... (answered by TimothyLamb)