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The equations of the lines which pass through the point (3, –2) and are inclined at 60° to the line \sqrt{3}x+y=1 is
A. y + 2 = 0, \sqrt{3}x-y-2-3\sqrt{3}=0
B. x – 2 = 0, \sqrt{3}x-y+2+3\sqrt{3}=0
C. \sqrt{3}x-y-2-3\sqrt{3}=0
D. None of these

Answers (1)

Given equation is \sqrt{3}x+y=1 and θ= 60  

 Slope of the equation \sqrt{3}x+y=1

y=1-\sqrt{3}x

  Slope of the equation m_{1}=-\sqrt{3}

 Let slope of the required line be m2   

Then \tan \theta = \left | \frac{\left ( m_{1}-m_{2} \right )}{1+m_{1}m_{2}} \right |

 Putting the values in the above equation we gettan 60^{\circ}=\left | \frac{-\sqrt{3}-m_{2}}{1+\left ( -\sqrt{3} \right )*m_{2}} \right |

 \sqrt{3}=\left | \frac{-\sqrt{3}-m_{2}}{1+\left ( -\sqrt{3} \right )*m_{2}} \right |

\sqrt{3}= \pm\left ( \frac{-\sqrt{3}-m_{2}}{1+\left ( -\sqrt{3} \right )*m_{2}} \right )

 Taking+sign we get  -\sqrt{3}-m_{2}=\sqrt{3}\left ( 1-\sqrt{3}m_{2} \right )

  -\sqrt{3}-m_{2}=\sqrt{3}-3m_{2}

3m_{2}-m_{2}=\sqrt{3}+\sqrt{3}

2m_{2}=2\sqrt{3}

   m_{2}=\sqrt{3}

  Taking -ve sign we get \sqrt{3}+m_{2}=\sqrt{3}\left ( 1-\sqrt{3}m_{2} \right )

   \sqrt{3}+m_{2}=\sqrt{3}-3m_{2}

3m_{2}+m_{2} =0

4m_{2} =0

 m2=0  

  Equation of line passing through (3,-2) with slope \sqrt{3} is  y-y1=m(x-x

 y-\left ( -2 \right )=\sqrt{3}\left ( x-3 \right )

y+2=\sqrt{3}x-3\sqrt{3}

   \sqrt{3}x-y-3\sqrt{3}-2=0

  and equation of line passing through (3, -2) with slope 0 is  y-y1=m(x-x1

 y-(-2)=0(x-3) 

 y+2=0 

  Hence, the required equations are \sqrt{3}x-y-\left ( 3\sqrt{3}+2 \right )=0   and y+2=0  

Hence, the correct option is (a)

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