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# Help needed

Kindly help in the following question. give rough idea.

Note by Mahimn Bhatt
2 years, 3 months ago

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Substitute $$x^2=9a^2-y^2$$ in the equation of ellipse and make $$D>0$$ · 2 years, 3 months ago

It does not contain any term in $$\large{y}$$ , just $$\large{y^{2}}$$ and some terms in $$\large{c}$$ and $$\large{a}$$ · 2 years, 3 months ago

$$\dfrac{9a^2-y^2}{4c^2}+\dfrac{y^2}{c^2}=1\\\Rightarrow 9a^2-y^2+4y^2=4c^2\\\Rightarrow 3y^2=4c^2-9a^2>0\\\Rightarrow 4c^2>9a^2$$ · 2 years, 3 months ago

Using this inequality, check out which option satisfies. · 2 years, 3 months ago

yes i m stuck now... · 2 years, 3 months ago