WBJEE · Maths · Ellipse
With origin as a foucs and x = 4 as corresponding directrix, a family of ellipse are drawn. Then the locus of an end of
minor axis is
- A a circle
- B a parabola
- C a straight line
- D a hyperbola
Answer & Solution
Correct Answer
(B) a parabola
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & h=-a e, k=b, \quad \frac{a}{e}-a e=4 \Rightarrow a\left(1-e^2\right)=4 e \Rightarrow \frac{b^2}{a}=4 e \\ & \Rightarrow b^2=4 a e \Rightarrow k^2=-4 h \Rightarrow y^2=-4 x \end{aligned}\) Which is a general conic and satisfying the condition of parabola.
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