Big Ideas Math Algebra 2, 2014
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Big Ideas Math Algebra 2, 2014 View details
4. Transformations of Exponential and Logarithmic Functions
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Exercise 23 Page 322

Start by performing a vertical stretch.

Transformation: Vertical stretch by a factor of 6, a horizontal translation 5 units to the left and a vertical translation 2 units down.
Graph:

Practice makes perfect
We want to graph the given exponential function as a transformation of its parent function. g(x)= 6(1/2)^(x+ 5)- 2 Looking at the function, we can see that it has been stretched by a factor of 6, translated 5 units to the left and translated 2 units down. Let's show the transformations one at a time.

Vertical Stretch

Let's start by considering the parent function f(x)=( 12)^x. If we multiply ( 12)^x by 6, we obtain a vertical stretch by a factor of 6. The resulting function is y=6( 12)^x.

Horizontal Translation

Now, we need to consider the function y=6( 12)^(x+5). This is a horizontal translation of y=6( 12)^x to the left by 5 units.

Vertical Translation

Finally, we will consider the function g(x)=6( 12)^(x+5)-2. This is a vertical translation of y=6( 12)^(x+5) down by 2 units.

Extra

Possible Transformations

The following table illustrates the general form for all possible transformations of functions.

Transformations of f(x)
Vertical Translations Translation up k units, k>0 y=f(x)+ k
Translation down k units, k>0 y=f(x)- k
Horizontal Translations Translation right h units, h>0 y=f(x- h)
Translation left h units, h>0 y=f(x+ h)
Vertical Stretch or Compression Vertical stretch, a>1 y= af(x)
Vertical compression, 0< a< 1 y= af(x)
Horizontal Stretch or Compression Horizontal stretch, b>1 y=f(1/bx)
Horizontal compression, 0< b<1 y=f(1/bx)
Reflections In the x-axis y=- f(x)
In the y-axis y=f(- x)