The joint equation of the lines through the origin trisecting angles in first and third equadrant is

The joint equation of the lines through the origin trisecting angles in first and third equadrant is
  1. $\sqrt{3}\left(x^{2}-y^{2}\right)+4 x y=0$
  2. $\sqrt{3}\left(x^{2}+y^{2}\right)-4 x y=0$
  3. $\sqrt{3}\left(x^{2}+y^{2}\right)+4 x y=0$
  4. $\sqrt{3}\left(x^{2}-y^{2}\right)-4 x y=0$

Solution

Equation line $\mathrm{L}_{1}$ is $\mathrm{y}=\tan 30^{\circ} \mathrm{x}$ $y=\frac{1}{\sqrt{3}} x \Rightarrow x-\sqrt{3} y=0 ...(1)$ Equation of line $\mathrm{L}_{2}$ is $\mathrm{y}=\tan 60^{\circ} \mathrm{x}$ $y=\sqrt{3} x \Rightarrow \sqrt{3} x-y=0 ...(2)$ $\therefore$ Joint equation is $(x-\sqrt{3} y)(\sqrt{3} x-y)=0 \Rightarrow \sqrt{3}\left(x^{2}+y^{2}\right)-4 x y=0$

Asked in: MHT CET 2020 (15 Oct Shift 2)

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