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Ch. 2 - Functions and Graphs
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 3, Problema 77a

Express the given function h as a composition of two functions ƒ and g so that h(x) = (fog) (x). h(x) = ∛(x² – 9)

Guida verificata passo dopo passo
1
Step 1: Understand the problem. The goal is to express the given function h(x) = ∛(x² – 9) as a composition of two functions ƒ(x) and g(x) such that h(x) = (ƒ ∘ g)(x), which means h(x) = ƒ(g(x)).
Step 2: Identify the inner function g(x). Look at the expression inside the cube root, x² – 9. This suggests that g(x) = x² – 9.
Step 3: Identify the outer function ƒ(x). The outer function operates on the result of g(x). Since h(x) = ∛(x² – 9), the cube root operation applies to g(x). Therefore, ƒ(x) = ∛x or equivalently ƒ(x) = x^(1/3).
Step 4: Verify the composition. Substitute g(x) into ƒ(g(x)) to ensure it matches h(x). ƒ(g(x)) = ƒ(x² – 9) = ∛(x² – 9), which is the original h(x).
Step 5: Conclude that the functions are ƒ(x) = x^(1/3) and g(x) = x² – 9, and their composition satisfies h(x) = (ƒ ∘ g)(x).

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Function Composition

Function composition involves combining two functions, where the output of one function becomes the input of another. In this context, if h(x) = (f o g)(x), it means h(x) can be expressed as f(g(x)). Understanding how to break down a function into simpler components is essential for solving the problem.
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