To find the function that represents the area of the rectangular garden given the length \( f(x) = x + 4 \) and the width \( g(x) = 2x - 1 \), we calculate the area \( A(x) \) by multiplying the two functions:
\[ A(x) = f(x) \cdot g(x) = (x + 4)(2x - 1) \]
Now we can expand this expression:
\[ A(x) = (x + 4)(2x - 1) = x(2x) + x(-1) + 4(2x) + 4(-1) = 2x^2 - x + 8x - 4 \] \[ A(x) = 2x^2 + 7x - 4 \]
Next, we need to determine the domain for the area function \( A(x) \). Since the length and width must be non-negative:
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For the length \( f(x) = x + 4 \): \[ x + 4 \geq 0 \implies x \geq -4 \]
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For the width \( g(x) = 2x - 1 \): \[ 2x - 1 \geq 0 \implies 2x \geq 1 \implies x \geq \frac{1}{2} \]
The more restrictive condition is \( x \geq \frac{1}{2} \).
Thus, the area function is: \[ A(x) = 2x^2 + 7x - 4 \]
And the domain of \( A(x) \) is: \[ x \geq \frac{1}{2} \]
So the correct response is: (f⋅g)(x)=2x²+7x−4 and the domain of (f⋅g)(x) is \( x \geq \frac{1}{2} \).