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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 36a

Find f+gf+g, f−gf-g, fgfg, and fg\(\frac{f}{g}\). Determine the domain for each function.
f(x)=6x2−x−1f\(\left\)(x\(\right\))=6x^2-x-1, g(x)=x−1g\(\left\)(x\(\right\))=x-1

Guida verificata passo dopo passo
1
Step 1: Understand the problem. You are tasked with finding the domain of the functions f(x) = 6x^2 - x - 1 and g(x) = x - 1, as well as the domain of their combinations: f + g, f - g, fg, and f/g. The domain of a function is the set of all x-values for which the function is defined.
Step 2: Analyze the domain of f(x). Since f(x) = 6x^2 - x - 1 is a polynomial, it is defined for all real numbers. Therefore, the domain of f(x) is all real numbers.
Step 3: Analyze the domain of g(x). The function g(x) = x - 1 is also a polynomial, so it is defined for all real numbers. Thus, the domain of g(x) is all real numbers.
Step 4: Determine the domain of f + g, f - g, and fg. Since these operations involve adding, subtracting, or multiplying two polynomials, the resulting functions are also polynomials. Therefore, the domain of f + g, f - g, and fg is all real numbers.
Step 5: Determine the domain of f/g. Division by zero is undefined, so we must exclude any x-values that make g(x) = 0. Solve g(x) = x - 1 = 0, which gives x = 1. Therefore, the domain of f/g is all real numbers except x = 1.

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