Most Important Selected Qs for JEE AdvancedMathematicsCircle
Let the circle S: x^2+y^2-a x-b y+c=0 intersects the pair of straight lines x y-4 x-3 y+12=0 orthogonally and the circle lies in the first quadrant. If S touches the circle S₁:(x-3)^2+y^2=r^2, r N , then find the sum of all possible values of r .
Correct answer
28
Step-by-step solution
aligned & x y-3 x-4 y+12=0 & (x-3)(y-4)=0 x=3 and y=4 & S: x^2+y^2-6 x-8 y+c=0 aligned For R=3, r=1 and 7 For R=2, r=2 and 6 For R=1, r=3 and 5 For R=0, r=4 Sum of all possible values of r=1+2+3+4+5+6+7=28