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If the area enclosed by y^(2)=2x and x^(...

If the area enclosed by `y^(2)=2x and x^(2)+4+4x=4y^(2)` is k square units, then the value of 3k is equal to

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To find the area enclosed by the curves \( y^2 = 2x \) and \( x^2 + 4 + 4x = 4y^2 \), we will follow these steps: ### Step 1: Identify the curves The first curve is given by: \[ y^2 = 2x \] This is a parabola that opens to the right. The second equation can be rearranged: \[ x^2 + 4 + 4x - 4y^2 = 0 \] We can rewrite it as: \[ x^2 + 4x + 4 - 4y^2 = 0 \] This can be factored as: \[ (x + 2)^2 - (2y)^2 = 0 \] This represents a pair of straight lines: \[ x + 2 - 2y = 0 \quad \text{and} \quad x + 2 + 2y = 0 \] or: \[ x = 2y - 2 \quad \text{and} \quad x = -2y - 2 \] ### Step 2: Find the points of intersection To find the points of intersection, we substitute \( y^2 = 2x \) into the line equations. For the first line \( x = 2y - 2 \): \[ y^2 = 2(2y - 2) \] \[ y^2 = 4y - 4 \] \[ y^2 - 4y + 4 = 0 \] \[ (y - 2)^2 = 0 \implies y = 2 \] Substituting \( y = 2 \) back to find \( x \): \[ x = 2(2) - 2 = 2 \] So one point of intersection is \( (2, 2) \). For the second line \( x = -2y - 2 \): \[ y^2 = 2(-2y - 2) \] \[ y^2 = -4y - 4 \] \[ y^2 + 4y + 4 = 0 \] \[ (y + 2)^2 = 0 \implies y = -2 \] Substituting \( y = -2 \) back to find \( x \): \[ x = -2(-2) - 2 = 2 \] So the other point of intersection is \( (2, -2) \). ### Step 3: Set up the integral for area The area \( A \) between the curves from \( y = -2 \) to \( y = 2 \) can be calculated as: \[ A = \int_{-2}^{2} \left[ (2y - 2) - \frac{y^2}{2} \right] dy \] ### Step 4: Calculate the integral Calculating the integral: \[ A = \int_{-2}^{2} \left( 2y - 2 - \frac{y^2}{2} \right) dy \] \[ = \int_{-2}^{2} \left( 2y - 2 - 0.5y^2 \right) dy \] Calculating the integral: \[ = \left[ y^2 - 2y - \frac{y^3}{6} \right]_{-2}^{2} \] Calculating at the limits: At \( y = 2 \): \[ = 2^2 - 2(2) - \frac{2^3}{6} = 4 - 4 - \frac{8}{6} = -\frac{8}{6} = -\frac{4}{3} \] At \( y = -2 \): \[ = (-2)^2 - 2(-2) - \frac{(-2)^3}{6} = 4 + 4 + \frac{8}{6} = 8 + \frac{4}{3} = \frac{24}{3} + \frac{4}{3} = \frac{28}{3} \] Now subtract: \[ A = \left( -\frac{4}{3} - \frac{28}{3} \right) = -\frac{32}{3} \] Since we are interested in the area, we take the absolute value: \[ A = \frac{32}{3} \] ### Step 5: Find \( k \) and \( 3k \) Thus, \( k = \frac{32}{3} \). Therefore: \[ 3k = 3 \times \frac{32}{3} = 32 \] ### Final Answer The value of \( 3k \) is \( \boxed{32} \).
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