To tackle this problem, we need to analyze the piecewise function given and then evaluate it at the specified points.
a. Choose the correct graph.
The piecewise function is defined as follows:
- \( f(x) = 7x - 12 \) if \( x \leq 3 \)
- \( f(x) = x^2 \) if \( x > 3 \)
Based on this definition:
- For \( x \leq 3 \), the function is linear (specifically, a line with a slope of 7).
- For \( x > 3 \), the function is a quadratic function that will be a parabola opening upwards.
From the graph descriptions, we can determine if they match the given piecewise function:
- Graph C describes a ray starting at the point (3, 9) and falling to the left, while a curve starts from (3, 9) and rises. This aligns with the description, as \( f(3) = 7(3)-12 = 9 \) and the next part for \( x > 3 \) gives \( f(4) = 4^2 = 16 \).
Thus, Graph C is correct.
b. Find \( f(1) \) and \( f(4) \).
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Finding \( f(1) \): Since \( 1 \leq 3 \), we use the first part of the piecewise function: \[ f(1) = 7(1) - 12 = 7 - 12 = -5 \]
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Finding \( f(4) \): Since \( 4 > 3 \), we use the second part of the piecewise function: \[ f(4) = 4^2 = 16 \]
c. State the domain of the function.
The function is defined for all real numbers since there are no restrictions on the input values for either piece of the function. Hence, the domain is:
\[ \text{Domain} = (-\infty, \infty) \]
Summary:
- Correct graph: Graph C
- \( f(1) = -5 \)
- \( f(4) = 16 \)
- Domain: \( (-\infty, \infty) \)