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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 39b

Find f−g and determine the domain for each function. f(x) = √x, g(x) = x − 4

Guida verificata passo dopo passo
1
Step 1: Understand the problem. We are tasked with finding the difference of two functions, denoted as (f − g)(x), which is defined as f(x) − g(x). Additionally, we need to determine the domain of the resulting function.
Step 2: Write the expression for (f − g)(x). Substitute the given functions f(x) = √x and g(x) = x − 4 into the formula for (f − g)(x): (f − g)(x) = f(x) − g(x) = √x − (x − 4).
Step 3: Simplify the expression for (f − g)(x). Distribute the negative sign across the terms in g(x): (f − g)(x) = √x − x + 4.
Step 4: Determine the domain of the resulting function. The domain is the set of all x-values for which the function is defined. For f(x) = √x, the square root requires x ≥ 0. For g(x) = x − 4, there are no restrictions. Therefore, the domain of (f − g)(x) is x ≥ 0.
Step 5: Express the domain in interval notation. Since x must be greater than or equal to 0, the domain is [0, ∞).

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