WBJEE · Maths · Hyperbola
The locus of the centre of the circles which touch both the circles \(x^{2}+y^{2}=a^{2}\) and \(x^{2}+y^{2}=4\)ax externally is
- A a circle
- B a parabola
- C an ellipse
- D a hyperbola
Answer & Solution
Correct Answer
(D) a hyperbola
Step-by-step Solution
Detailed explanation
Hint: Let, centre \(\equiv(\mathrm{h}, \mathrm{k})\) and radius \(=\mathrm{r}\) for the variable circle So, using \(\mathrm{C}_{1} \mathrm{C}_{2}=\mathrm{r}_{1}+\mathrm{r}_{2}\) for both cases we have:…
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