Big Ideas Math Integrated I, 2016
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Big Ideas Math Integrated I, 2016 View details
1. Exponential Functions
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Exercise 53 Page 280

Start by making a table of values for both functions.

Graph:

Table:

Function y-intercept Domain Range
f(x)=- 2^x (0, - 1) All real numbers y< 0
g(x)=- 2^x-3 (0, - 4) All real numbers y< - 3
Practice makes perfect
We want to draw graphs of the exponential functions. ccc f(x)=- 2^x & & & g(x)=- 2^x-3 To do so, we will first make a table of values.
x - 1 0 1 2
f(x)=- 2^x - 2^(- 1)= - 1/2 - 2^0= - 1 - 2^1= - 2 - 2^2= - 4
g(x)=- 2^x-3 - 2^(- 1)-3= - 3 1/2 - 2^0-3= - 4 - 2^1-3= - 5 - 2^2-3= - 7
  • The ordered pairs ( - 3, - 18), ( 0, - 1), and ( 3, - 8) all lie on the function f(x)=- 2^x.
  • The ordered pairs ( - 3, - 3 18), ( 0, - 4), and ( 3, - 11) all lie on the function g(x)=- 2^x-3.
Now, we will plot and connect these points with a smooth curve.

We see that g(x)=- 2^x-3 is a vertical translation of f(x)=- 2^x down by 3 units. Hence, the y-intercept of g is 3 units below the y-intercept of f. Both functions have the same domain — all real numbers. The range of f is y< 0, and the range of g is y < - 3. Let's show them in a table.

Function y-intercept Domain Range
f(x)=- 2^x (0, - 1) All real numbers y< 0
g(x)=- 2^x-3 (0, - 4) All real numbers y< - 3