The locus of the point of intersection of the lines $\left( {\sqrt 3 } \right)kx + ky - 4\sqrt 3 = 0$ and $\sqrt 3 x - y - 4\left( {\sqrt 3 } \right)k = 0$ is a conic, whose eccentricity is _________.
Answer (integer)
2
Solution
$\sqrt 3 kx + ky = 4\sqrt 3$ ........(1)<br><br>$\sqrt 3 kx - ky = 4\sqrt 3 {k^2}$ ....... (2)<br><br>Adding equation (1) & (2)<br><br>$2\sqrt 3 kx = 4\sqrt 3 ({k^2} + 1)$<br><br>$x = 2\left( {k + {1 \over k}} \right)$ ......... (3)<br><br>Substracting equation (1) & (2)<br><br>$y = 2\sqrt 3 \left( {{1 \over k} - k} \right)$ ........(4)<br><br>$\therefore$ ${{{x^2}} \over 4} - {{{y^2}} \over {12}} = 4$<br><br>${{{x^2}} \over {16}} - {{{y^2}} \over {48}} = 1$ (Hyperbola)<br><br>$\therefore$ ${e^2} = 1 + {{48} \over {16}}$<br><br>$\Rightarrow$ $e = 2$
About this question
Subject: Mathematics · Chapter: Conic Sections · Topic: Parabola
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