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Let g, f:R rarr R be defined by g(x)=(...

Let `g, f:R rarr R` be defined by
`g(x)=(x+2)/(3), f(x)=3x-2`. Write fog (x)

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The correct Answer is:
To find the composition of the functions \( f \) and \( g \), denoted as \( f \circ g(x) \), we need to follow these steps: 1. **Identify the functions**: - We have \( g(x) = \frac{x + 2}{3} \) - We have \( f(x) = 3x - 2 \) 2. **Substitute \( g(x) \) into \( f(x) \)**: - We need to find \( f(g(x)) \). This means we will substitute \( g(x) \) into \( f(x) \). - So, we will replace \( x \) in \( f(x) \) with \( g(x) \): \[ f(g(x)) = f\left(\frac{x + 2}{3}\right) \] 3. **Evaluate \( f \left( \frac{x + 2}{3} \right) \)**: - Now, we will use the definition of \( f(x) \): \[ f(t) = 3t - 2 \] - Here, we let \( t = g(x) = \frac{x + 2}{3} \). Therefore: \[ f\left(\frac{x + 2}{3}\right) = 3\left(\frac{x + 2}{3}\right) - 2 \] 4. **Simplify the expression**: - Now, we simplify: \[ f\left(\frac{x + 2}{3}\right) = \frac{3(x + 2)}{3} - 2 = (x + 2) - 2 \] - This simplifies to: \[ x + 2 - 2 = x \] 5. **Final result**: - Therefore, the composition \( f \circ g(x) \) is: \[ f \circ g(x) = x \] ### Final Answer: \[ f \circ g(x) = x \]
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