The equation of tangent to the circle ${x^2} + {y^2} = {a^2}$ parallel to $y = mx + c$ is
The equation of tangent to the circle ${x^2} + {y^2} = {a^2}$ parallel to $y = mx + c$ is
- A
$y = mx \pm \sqrt {1 + {m^2}} $
- B
$y = mx \pm a\sqrt {1 + {m^2}} $
- C
$x = my \pm a\sqrt {1 + {m^2}} $
- D
None of these
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- [IIT 2020]
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