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Let $f(\alpha)$ denote the area of the region in the first quadrant bounded by $x = 0, x = 1, y^2 = x$ and $y = |\alpha x - 5| - |1 - \alpha x| + \alpha x^2$. Then $(f(0) + f(1))$ is equal to

The correct answer is
12

Area Calculation for α = 0

The area function $f(\alpha)$ is defined for the region in the first quadrant bounded by $x=0$, $x=1$, $y=\sqrt{x}$ (from $y^2=x$), and $y = |\alpha x - 5| - |1 - \alpha x| + \alpha x^2$.

For $\alpha = 0$, the upper boundary simplifies: $y = |0 \cdot x - 5| - |1 - 0 \cdot x| + 0 \cdot x^2 = |-5| - |1| = 5 - 1 = 4$. The area $f(0)$ integrates the difference between the upper curve ($y=4$) and the lower curve ($y=\sqrt{x}$) from $x=0$ to $x=1$.

Integral Setup: $f(0) = \int_{0}^{1} (4 - \sqrt{x}) \, dx$

Evaluation: $f(0) = \int_{0}^{1} (4 - x^{1/2}) \, dx = \left[ 4x - \frac{2}{3}x^{3/2} \right]_{0}^{1} = \left( 4(1) - \frac{2}{3}(1)^{3/2} \right) - (0) = 4 - \frac{2}{3} = \frac{10}{3}$

Area Calculation for α = 1

For $\alpha = 1$, the upper boundary function is $y = |x - 5| - |1 - x| + x^2$. In the interval $x \in [0, 1]$: $|x - 5| = -(x - 5) = 5 - x$ and $|1 - x| = 1 - x$.

Substituting these simplifies the function to $y = (5 - x) - (1 - x) + x^2 = 4 + x^2$. The area $f(1)$ integrates the difference between the upper curve ($y=4+x^2$) and the lower curve ($y=\sqrt{x}$) from $x=0$ to $x=1$.

Integral Setup: $f(1) = \int_{0}^{1} ((4 + x^2) - \sqrt{x}) \, dx$

Evaluation: $f(1) = \int_{0}^{1} (4 + x^2 - x^{1/2}) \, dx = \left[ 4x + \frac{x^3}{3} - \frac{2}{3}x^{3/2} \right]_{0}^{1} = \left( 4 + \frac{1}{3} - \frac{2}{3} \right) - (0) = 4 - \frac{1}{3} = \frac{11}{3}$

Final Sum: f(0) + f(1)

Summing the calculated areas: $f(0) + f(1) = \frac{10}{3} + \frac{11}{3}$

$f(0) + f(1) = \frac{21}{3} = 7$

The final result is 7.

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