Transformations of Functions
We are given the graph of a function y=h(x).
A)
We must apply transformations to get the funcion:
y=2h(x + 4) + 3
The first transformation must be a translation by 4 units to the left. That will give us h(x + 4).
Secondly, we must stretch the function obtained above by a factor of 2 to get:
2h(x + 4).
Finally, we must translate the function above by 3 units up and get the required result:
y=2h(x + 4) + 3
B)
Let's call the points of the original function:
P(-2,-1) Q(0,1) R(2,-3)
Now we map those points to the transformed points by using the rules:
Translate 4 units left
Stretch by a factor of 2
Translate 3 units up
The point P has x=-2 and will map to:
y = 2(-2+4)+3 = 2(2) + 3 = 7
P'(-2,7)
The point Q has x=0 and will map to:
y = 2(0+4)+3 = 2(4) + 3 = 11
Q'(0,11)
The point R has x=2 and will map to:
y = 2(2+4)+3 = 2(6) + 3 = 15
P'(2,15)
We use the mapped points to produce the new graph as follows: