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Compute some properties of an ellipse with a given Cartesian equation

Find the coordinates of the center, the foci, and the vertices, sketch the curve, and determine the eccentricity of the ellipse given by the equation

    \[ 4y^2 + 3x^2 = 1. \]


First, we have

    \[ 4y^2 + 3x^2 = 1 \quad \implies \quad \frac{x^2}{\left( \frac{1}{\sqrt{3}} \right)^2} + \frac{y^2}{ \left( \frac{1}{2} \right)^2} = 1. \]

So, this is the equation for an ellipse in standard form with center at (0,0) and with a = \frac{1}{\sqrt{3}} and b = \frac{1}{2}. Therefore,

    \[ c = \sqrt{a^2 - b^2} = \sqrt{\frac{1}{3} - \frac{1}{4}} = \sqrt{\frac{1}{12}} = \frac{\sqrt{3}}{6}. \]

So, the foci are

    \[ \left( \frac{\sqrt{3}}{6}, 0\right) \qquad \text{and} \qquad \left( -\frac{\sqrt{3}}{6}, 0 \right). \]

Then, the vertices are pm aN, which are

    \[ \left( \frac{\sqrt{3}}{3}, 0 \right), \qquad \text{and} \qquad \left( - \frac{\sqrt{3}}{3}, 0 \right). \]

Finally, we compute the eccentricity,

    \[ c = ea \quad \implies \quad \frac{\sqrt{3}}{6} = \frac{1}{\sqrt{3}} e \quad \implies \quad e = \frac{1}{2}.\]

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