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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 65

Find a. (fog) (x) b. (go f) (x) c. (fog) (2) d. (go f) (2).
f(x) = 1/x, g(x)= 1/x

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Step 1: Understand the composition of functions. The notation (f ∘ g)(x) means f(g(x)), which involves substituting g(x) into f(x). Similarly, (g ∘ f)(x) means g(f(x)), which involves substituting f(x) into g(x).
Step 2: For part (a), calculate (f ∘ g)(x). Substitute g(x) = 1/x into f(x) = 1/x. This gives f(g(x)) = f(1/x). Replace x in f(x) with 1/x to get the expression for (f ∘ g)(x).
Step 3: For part (b), calculate (g ∘ f)(x). Substitute f(x) = 1/x into g(x) = 1/x. This gives g(f(x)) = g(1/x). Replace x in g(x) with 1/x to get the expression for (g ∘ f)(x).
Step 4: For part (c), evaluate (f ∘ g)(2). Use the expression for (f ∘ g)(x) derived in part (a) and substitute x = 2. Simplify the resulting expression.
Step 5: For part (d), evaluate (g ∘ f)(2). Use the expression for (g ∘ f)(x) derived in part (b) and substitute x = 2. Simplify the resulting expression.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
2m

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 understanding how to manipulate and evaluate the functions in sequence.
추천 영상:
가이드 코스
4:56
Function Composition

Evaluating Functions

Evaluating functions means substituting a specific value into the function to find the output. For example, if f(x) = 1/x, evaluating f(2) involves substituting 2 for x, resulting in f(2) = 1/2. 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

Reciprocal Functions

Reciprocal functions are functions of the form f(x) = 1/x, which are defined for all x except zero. They exhibit unique properties, such as having vertical asymptotes at x = 0 and being symmetric about the line y = x. Understanding the behavior of reciprocal functions is important for accurately performing the compositions and evaluations in the problem.
추천 영상:
가이드 코스
4:56
Function Composition