A) \[3\sqrt{2}\]
B) \[3\]
C) \[2\sqrt{2}\]
D) \[2\]
Correct Answer: A
Solution :
Equation of circle can be written as \[{{\left( x1 \right)}^{2}}+{{\left( y1 \right)}^{2}}+\lambda \left( xy \right)=0\] It passes through (1, -3) \[16+\lambda \left( 4 \right)=0\Rightarrow \lambda =-4\] So \[{{\left( x1 \right)}^{2}}+{{\left( y1 \right)}^{2}}4\left( xy \right)=0\] \[\Rightarrow {{x}^{2}}+{{y}^{2}}6x+2y+2=0\] \[\Rightarrow r=2\sqrt{2}\] (correct key is b)You need to login to perform this action.
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