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The area bounded by the normal at (1, 2...

The area bounded by the normal at `(1, 2)` to the parabole `y^(2)=4x`, x-axis and the curve is …...........

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To find the area bounded by the normal at the point (1, 2) to the parabola \(y^2 = 4x\), the x-axis, and the curve itself, we will follow these steps: ### Step 1: Find the slope of the tangent to the parabola at the point (1, 2). The equation of the parabola is given by: \[ y^2 = 4x \] To find the slope of the tangent, we differentiate the equation with respect to \(x\): \[ \frac{d(y^2)}{dx} = \frac{d(4x)}{dx} \implies 2y \frac{dy}{dx} = 4 \implies \frac{dy}{dx} = \frac{4}{2y} = \frac{2}{y} \] At the point (1, 2), substituting \(y = 2\): \[ \frac{dy}{dx} = \frac{2}{2} = 1 \] ### Step 2: Find the slope of the normal line. The slope of the normal line is the negative reciprocal of the slope of the tangent: \[ \text{slope of normal} = -\frac{1}{\frac{dy}{dx}} = -1 \] ### Step 3: Write the equation of the normal line. Using the point-slope form of the equation of a line: \[ y - y_1 = m(x - x_1) \] where \(m\) is the slope and \((x_1, y_1) = (1, 2)\): \[ y - 2 = -1(x - 1) \implies y - 2 = -x + 1 \implies x + y = 3 \] ### Step 4: Find the points of intersection between the normal line and the parabola. We need to find the intersection of the line \(x + y = 3\) with the parabola \(y^2 = 4x\). From the line equation, we can express \(y\): \[ y = 3 - x \] Substituting into the parabola equation: \[ (3 - x)^2 = 4x \] Expanding and rearranging: \[ 9 - 6x + x^2 = 4x \implies x^2 - 10x + 9 = 0 \] ### Step 5: Solve the quadratic equation. Using the quadratic formula \(x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\): \[ x = \frac{10 \pm \sqrt{(-10)^2 - 4 \cdot 1 \cdot 9}}{2 \cdot 1} = \frac{10 \pm \sqrt{100 - 36}}{2} = \frac{10 \pm \sqrt{64}}{2} = \frac{10 \pm 8}{2} \] Thus, the solutions are: \[ x = \frac{18}{2} = 9 \quad \text{and} \quad x = \frac{2}{2} = 1 \] ### Step 6: Find the corresponding \(y\) values. For \(x = 1\): \[ y = 3 - 1 = 2 \] For \(x = 9\): \[ y = 3 - 9 = -6 \] ### Step 7: Calculate the area bounded by the curves. We need to find the area between the parabola and the normal line from \(x = 1\) to \(x = 9\). The area \(A\) can be computed as: \[ A = \int_{1}^{9} \left( (3 - x) - \sqrt{4x} \right) \, dx \] ### Step 8: Evaluate the integral. Calculating the integral: 1. The integral of \(3 - x\) from 1 to 9: \[ \int_{1}^{9} (3 - x) \, dx = \left[ 3x - \frac{x^2}{2} \right]_{1}^{9} = \left( 27 - \frac{81}{2} \right) - \left( 3 - \frac{1}{2} \right) = \left( 27 - 40.5 \right) - \left( 3 - 0.5 \right) = -13.5 - 2.5 = -16 \] 2. The integral of \(\sqrt{4x} = 2\sqrt{x}\): \[ \int_{1}^{9} 2\sqrt{x} \, dx = \left[ \frac{4}{3} x^{3/2} \right]_{1}^{9} = \frac{4}{3} \left( 27 - 1 \right) = \frac{4}{3} \cdot 26 = \frac{104}{3} \] ### Step 9: Combine the areas. The total area \(A\) is: \[ A = \left( -16 \right) - \left( -\frac{104}{3} \right) = -16 + \frac{104}{3} = \frac{-48 + 104}{3} = \frac{56}{3} \] ### Final Answer: The area bounded by the normal at (1, 2) to the parabola \(y^2 = 4x\), the x-axis, and the curve is: \[ \frac{56}{3} \text{ square units.} \]
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