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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 1

Find f(g(x)) and g (f(x)) and determine whether each pair of functions ƒ and g are inverses of each other. f(x) = 4x and g(x) = x/4

Guida verificata passo dopo passo
1
First, find the composition \( f(g(x)) \). This means you substitute \( g(x) \) into \( f(x) \). Since \( f(x) = 4x \) and \( g(x) = \frac{x}{4} \), write \( f(g(x)) = f\left( \frac{x}{4} \right) \).
Next, evaluate \( f\left( \frac{x}{4} \right) \) by replacing the \( x \) in \( f(x) = 4x \) with \( \frac{x}{4} \). This gives \( f\left( \frac{x}{4} \right) = 4 \times \frac{x}{4} \).
Simplify the expression \( 4 \times \frac{x}{4} \) by canceling the 4 in numerator and denominator, resulting in \( f(g(x)) = x \).
Now, find the composition \( g(f(x)) \). Substitute \( f(x) \) into \( g(x) \). Since \( g(x) = \frac{x}{4} \) and \( f(x) = 4x \), write \( g(f(x)) = g(4x) \).
Evaluate \( g(4x) \) by replacing \( x \) in \( g(x) = \frac{x}{4} \) with \( 4x \), giving \( g(4x) = \frac{4x}{4} \). Simplify this to get \( g(f(x)) = x \). Since both compositions \( f(g(x)) \) and \( g(f(x)) \) equal \( x \), the functions \( f \) and \( g \) are inverses of each other.

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