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प्रश्न
The radius of the circle represented by the equation 3x2 + 3y2 + λxy + 9x + (λ − 6) y + 3 = 0 is
पर्याय
\[\frac{3}{2}\]
\[\frac{\sqrt{17}}{2}\]
2/3
none of these
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उत्तर
\[\frac{3}{2}\]
The equation of the circle is 3x2 + 3y2 + λxy + 9x + (λ − 6) y + 3 = 0.
∴ Coefficient of xy = 0
\[\Rightarrow \lambda = 0\]
\[\therefore 3 x^2 + 3 y^2 + 9x - 6y + 3 = 0\]
\[ \Rightarrow x^2 + y^2 + 3x - 2y + 1 = 0\]
Therefore, the radius of the circle is
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