Calculate the area enclosed between the lines \( y = 2x + 3 \) and \( y = x^2 \).
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To find the area enclosed between the lines \( y = 2x + 3 \) and \( y = x^2 \), we first need to determine the points of intersection. We set the equations equal to each other: \[ 2x + 3 = x^2 \] Rearranging gives us: \[ x^2 - 2x - 3 = 0 \] Factoring the quadratic equation, we have: \[ (x - 3)(x + 1) = 0 \] This gives us the points of intersection at \( x = 3 \) and \( x = -1 \). Next, we need to find the area between the curves from \( x = -1 \) to \( x = 3 \). The area \( A \) can be calculated by the integral of the top curve minus the bottom curve: \[ A = \int_{-1}^{3} (2x + 3 - x^2) \, dx \] Now we can simplify the integrand: \[ 2x + 3 - x^2 = -x^2 + 2x + 3 \] We will compute the definite integral: \[ A = \int_{-1}^{3} (-x^2 + 2x + 3) \, dx \] Calculating the integral: \[ \int (-x^2 + 2x + 3) \, dx = -\frac{x^3}{3} + x^2 + 3x \] Next, we evaluate this from \( x = -1 \) to \( x = 3 \): \[ A = \left[ -\frac{3^3}{3} + 3^2 + 3 \cdot 3 \right] - \left[ -\frac{(-1)^3}{3} + (-1)^2 + 3(-1) \right] \] Calculating the first term: \[ -\frac{27}{3} + 9 + 9 = -9 + 18 = 9 \] Calculating the second term: \[ -\left(-\frac{-1}{3} + 1 - 3\right) = \frac{1}{3} - 2 = -\frac{5}{3} \] Now, adding these results: \[ A = 9 + \frac{5}{3} = 9 + 1.67 \approx 10.67 \] To express \( 9 + \frac{5}{3} \) as a single fraction: \[ A = \frac{27}{3} + \frac{5}{3} = \frac{32}{3} \] Thus, the area enclosed between the lines \( y = 2x + 3 \) and \( y = x^2 \) is: \[ \boxed{\frac{32}{3}} \]