AP EAMCET202021 Sep 2020Morning ShiftMathematicsCircleActual
Find the equation of circle having normals ((x-1)(y-2)=0 ) and a tangent (3 x+4 y=6 ) ?
Options
- A((x-1)^2+(y-2)^2=1 )
- B((x-2)^2+(y-1)^2=1 )
- C((x+1)^2+(y+2)^2=1 )
- D((x+2)^2+(y+1)^2=1 )
Correct answer
A. ((x-1)^2+(y-2)^2=1 )
Step-by-step solution
The equation of normals to the circle are (x-1=0 ) and (y-2=0 ), so centre of the circle is ((1,2) ) and since (3 x+4 y=6 ) is the tangent to the circle so radius (r= 3+8-6 3^2+4^2 =1 ) ( ) Equation of required circle is ((x-1)^2+(y-2)^2=1 ) Hence, option (a) is correct.