Substitute \(x^2=9a^2-y^2\) in the equation of ellipse and make \(D>0\)
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Pranjal Jain
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2 years, 1 month ago

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@Pranjal Jain
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It does not contain any term in \(\large{y}\) , just \(\large{y^{2}} \) and some terms in \(\large{c}\) and \(\large{a}\)
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Mahimn Bhatt
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2 years, 1 month ago

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@Mahimn Bhatt
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\(\dfrac{9a^2-y^2}{4c^2}+\dfrac{y^2}{c^2}=1\\\Rightarrow 9a^2-y^2+4y^2=4c^2\\\Rightarrow 3y^2=4c^2-9a^2>0\\\Rightarrow 4c^2>9a^2\)
–
Pranjal Jain
·
2 years, 1 month ago

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TopNewestSubstitute \(x^2=9a^2-y^2\) in the equation of ellipse and make \(D>0\) – Pranjal Jain · 2 years, 1 month ago

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– Mahimn Bhatt · 2 years, 1 month ago

It does not contain any term in \(\large{y}\) , just \(\large{y^{2}} \) and some terms in \(\large{c}\) and \(\large{a}\)Log in to reply

– Pranjal Jain · 2 years, 1 month ago

\(\dfrac{9a^2-y^2}{4c^2}+\dfrac{y^2}{c^2}=1\\\Rightarrow 9a^2-y^2+4y^2=4c^2\\\Rightarrow 3y^2=4c^2-9a^2>0\\\Rightarrow 4c^2>9a^2\)Log in to reply

– Pranjal Jain · 2 years, 1 month ago

Using this inequality, check out which option satisfies.Log in to reply

– Mahimn Bhatt · 2 years, 1 month ago

yes i m stuck now...Log in to reply

@Karan Siwach @Sandeep Bhardwaj @Ronak Agarwal @Pranjal Jain – Mahimn Bhatt · 2 years, 1 month ago

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