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Ch. 2 - Graphs and Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 3, Problem 64

Let ƒ(x)=2x-3 and g(x)=-x+3. Find each function value. See Example 5.
(gg)(2)(g∘g)(-2)

Verified step by step guidance
1
Understand that the notation \((g \circ g)(-2)\) means you need to find \(g(g(-2))\), which is the composition of the function \(g\) with itself, evaluated at \(-2\).
First, find the inner function value \(g(-2)\) by substituting \(-2\) into the function \(g(x) = -x + 3\). This means calculating \(g(-2) = -(-2) + 3\).
Simplify the expression from the previous step to get the value of \(g(-2)\).
Next, take the result from step 3 and substitute it back into the function \(g(x)\) to find \(g(g(-2))\). This means calculating \(g(\text{result from step 3}) = -\text{result} + 3\).
Simplify the expression from step 4 to find the final value of \((g \circ g)(-2)\).

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Function Composition

Function composition involves applying one function to the result of another, denoted as (g∘g)(x) = g(g(x)). It requires evaluating the inner function first, then using that output as the input for the outer function.
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Evaluating Functions at a Given Input

Evaluating a function at a specific input means substituting the input value into the function's formula and simplifying to find the output. For example, g(-2) means replacing x with -2 in g(x).
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Linear Functions

Linear functions have the form f(x) = mx + b, where m and b are constants. They produce straight-line graphs and are straightforward to evaluate and compose, as seen in the given functions f(x) = 2x - 3 and g(x) = -x + 3.
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