MCQ
Equation of a circle whose centre is origin and radius is equal to the distance between the lines $x = 1$ and $x = - 1$ is
- A${x^2} + {y^2} = 1$
- B${x^2} + {y^2} = \sqrt 2 $
- ✓${x^2} + {y^2} = 4$
- D${x^2} + {y^2} = - 4$
✓
Answer
Correct option: C.
${x^2} + {y^2} = 4$
c
(c) Radius = $2, C\ (0, 0)$
(c) Radius = $2, C\ (0, 0)$
Equation of circle can be found from this.
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