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Ch. 2 - Graphs and Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 3

Without using paper and pencil, evaluate each expression given the following functions. ƒ(x)=x+1ƒ(x)=x+1 and g(x)=x2g(x)=x^2
(ƒg)(2)

검증된 단계별 안내
1
Understand that the notation \((\f g)(2)\) means the composition of functions \(f\) and \(g\) evaluated at \(x=2\), which is \(f(g(2))\).
First, evaluate the inner function \(g(2)\) by substituting \(2\) into \(g(x) = x^2\), so calculate \(g(2) = 2^2\).
Next, take the result from \(g(2)\) and substitute it into the function \(f(x) = x + 1\), so compute \(f(g(2)) = f(2^2) = f(4)\).
Evaluate \(f(4)\) by substituting \(4\) into \(f(x) = x + 1\), which means calculating \(4 + 1\).
The final value of \((f g)(2)\) is the result of \(f(4)\), which completes the evaluation of the composition.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
1m

주요 개념

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

Function Composition

Function composition involves applying one function to the result of another, denoted as (f∘g)(x) = f(g(x)). It means you first evaluate g at x, then use that output as the input for f. Understanding this process is essential to correctly evaluate composite functions.
추천 영상:
4:56
Function Composition

Evaluating Functions

Evaluating a function means substituting a specific value for the variable and simplifying the expression. For example, if f(x) = x + 1, then f(3) = 3 + 1 = 4. This skill is necessary to find the value of functions at given points.
추천 영상:
4:26
Evaluating Composed Functions

Order of Operations in Composite Functions

When evaluating composite functions like (f∘g)(2), you must first compute g(2) before applying f to that result. This order ensures accurate evaluation and avoids mistakes, as the inner function's output becomes the input for the outer function.
추천 영상:
4:56
Function Composition