Find \( f(g(x)) \) and \( g(f(x)) \) and determine whether the pair of functions \( f \) and \( g \) are inverses of each other. \( f(x)=9 x-8 \) and \( g(x)=\frac{x+9}{8} \) a. \( f(g(x))=\square \) (Simplify your answer. Use integers or fractions for any numbers in the expression.)
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To find \( f(g(x)) \), we first need to substitute \( g(x) \) into \( f(x) \). We have: \[ g(x) = \frac{x + 9}{8} \] Now, substituting \( g(x) \) into \( f(x) \): \[ f(g(x)) = f\left(\frac{x + 9}{8}\right) = 9\left(\frac{x + 9}{8}\right) - 8 \] Now we can simplify it: \[ = \frac{9(x + 9)}{8} - 8 = \frac{9x + 81}{8} - \frac{64}{8} = \frac{9x + 81 - 64}{8} = \frac{9x + 17}{8} \] So, \[ f(g(x)) = \frac{9x + 17}{8}. \] Now, let's find \( g(f(x)) \) by substituting \( f(x) \) into \( g(x) \): \[ f(x) = 9x - 8 \] Substituting this into \( g(x) \): \[ g(f(x)) = g(9x - 8) = \frac{(9x - 8) + 9}{8} = \frac{9x + 1}{8}. \] So, \[ g(f(x)) = \frac{9x + 1}{8}. \] Now, let's determine if \( f \) and \( g \) are inverses of each other. For \( f \) and \( g \) to be inverses, we need: 1. \( f(g(x)) = x \) 2. \( g(f(x)) = x \) From our calculations: - \( f(g(x)) = \frac{9x + 17}{8} \) (not equal to \( x \)) - \( g(f(x)) = \frac{9x + 1}{8} \) (not equal to \( x \)) Thus, \( f \) and \( g \) are not inverses of each other.