Most Important Selected Qs for JEE AdvancedMathematicsCircle
If S: x^2+y^2+2 g x+2 f y+c=0 intersects both the lines x y-3 x=0 orthogonally and touches the circle x^2+y^2-6 x-12 y+36=0 externally, then:
Options
- AS neither intersects nor touches the x -axis
- Bradius of the circle S lies in (1,2)
- Cradius of the circle S lies in (2,3)
- Dequation of the transverse common tangent to both the circle is x+y-3 2 -9=0
Correct answer
B. radius of the circle S lies in (1,2)
Step-by-step solution
x(y-3)=0 (0,3) is the centre aligned & c₁ c₂=r₁+r₂ & 9+9 =r+3 & r=3( 2 -1) 1.2 aligned Transverse common tangent to both the circles x+y+k=0 gathered applying p=r k= 3 2 -9 x+y+3 2 -9=0 or x+y-3 2 -9=0 (rejected) gathered