McGraw Hill Integrated II, 2012
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McGraw Hill Integrated II, 2012 View details
Study Guide and Review
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Exercise 10 Page 265

Start by making a table of values.

Domain: {all real numbers}
Range: {f(x) | f(x)>3}

Practice makes perfect

Let's begin by graphing the function. Then we will state its domain and range.

Graphing the Function

We want to draw a graph of the given exponential function. f(x)=3/5( 2/3 )^(x-2)+3

Because the base of our function is less than 1, we know that it is an exponential decay function. Let's start by making a table of values.

x 3/5(2/3)^(x-2)+3 y=3/5(2/3)^(x-2)+3
- 3 3/5(2/3)^(- 3-2)+3 7.556 ...
- 2 3/5(2/3)^(- 2-2)+3 6.0375
- 1 3/5(2/3)^(- 1-2)+3 5.025
0 3/5(2/3)^(0-2)+3 4.35
1 3/5(2/3)^(1-2)+3 3.9
2 3/5(2/3 )^(2-2)+3 3.6

All of the ordered pairs ( - 3, 7.556), ( - 2, 6.0375), ( - 1, 5.025), ( 0, 4.35), ( 1, 3.9) and ( 2, 3.6) belong to the graph of our function. Now, we will plot and connect these points with a smooth curve.

Determining the Domain and Range

Unless a restriction is specifically stated, the domain of any exponential function is all real numbers. The graph of our function is above the line y=3, so the range is all real numbers that are greater than 3. Domain:& { all real numbers } Range:& {f(x) | f(x) >3 }