Length of the tangent from $({x_1},{y_1})$ to the circle ${x^2} + {y^2} + 2gx + 2fy + c = 0$ is
Length of the tangent from $({x_1},{y_1})$ to the circle ${x^2} + {y^2} + 2gx + 2fy + c = 0$ is
- A
${(x_1^2 + y_1^2 + 2g{x_1} + 2f{y_1} + c)^{1/2}}$
- B
${(x_1^2 + y_1^2)^{1/2}}$
- C
${[{({x_1} + g)^2} + {({y_1} + f)^2}]^{1/2}}$
- D
None of these
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