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Ch. 2 - Functions and Graphs
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 63a

Find a. (fog) (x) b. (go f) (x) c. (fog) (2) d. (go f) (2).
f(x) = 2x-3, g(x) = (x+3)/2

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Step 1: Understand the problem. You are tasked with finding the compositions of two functions, f(x) = 2x - 3 and g(x) = (x + 3)/2, in four parts: (fog)(x), (gof)(x), (fog)(2), and (gof)(2). Composition of functions means substituting one function into another.
Step 2: To find (fog)(x), substitute g(x) into f(x). Replace every instance of 'x' in f(x) = 2x - 3 with g(x) = (x + 3)/2. This gives f(g(x)) = 2((x + 3)/2) - 3. Simplify the expression.
Step 3: To find (gof)(x), substitute f(x) into g(x). Replace every instance of 'x' in g(x) = (x + 3)/2 with f(x) = 2x - 3. This gives g(f(x)) = ((2x - 3) + 3)/2. Simplify the expression.
Step 4: To find (fog)(2), use the result from Step 2 and substitute x = 2 into the simplified expression for (fog)(x). Simplify the result.
Step 5: To find (gof)(2), use the result from Step 3 and substitute x = 2 into the simplified expression for (gof)(x). Simplify the result.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Function Composition

Function composition involves combining two functions to create a new function. If f(x) and g(x) are two functions, the composition (fog)(x) means applying g first and then f to the result, expressed as f(g(x)). This concept is essential for solving the given exercises, as it requires evaluating the output of one function as the input for another.
추천 영상:
가이드 코스
4:56
Function Composition

Evaluating Functions

Evaluating functions means substituting a specific value into a function to find its output. For example, if f(x) = 2x - 3, to evaluate f(2), you replace x with 2, resulting in f(2) = 2(2) - 3 = 1. This skill is crucial for calculating the values of (fog)(2) and (go f)(2) in the exercises.
추천 영상:
가이드 코스
4:26
Evaluating Composed Functions

Algebraic Manipulation

Algebraic manipulation refers to the process of rearranging and simplifying expressions using algebraic rules. This includes operations like addition, subtraction, multiplication, and division of functions. Mastery of these techniques is necessary to simplify the results of function compositions and to ensure accurate evaluations in the exercises.
추천 영상:
가이드 코스
05:09
Introduction to Algebraic Expressions