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If \(\lim _{x \rightarrow 0} \frac{((a-n) n x-\tan x) \sin n x}{x^2}=0\), where \(n\) is non-zero real number, then a is equal to
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Verified Answer
The correct answer is:
\(\mathrm{n}+\frac{1}{\mathrm{n}}\)
\(\begin{aligned}
& \lim _{\mathrm{x} \rightarrow 0} \mathrm{n} \frac{\sin \mathrm{nx}}{\mathrm{nx}} \cdot \lim _{\mathrm{x} \rightarrow 0}\left((\mathrm{a}-\mathrm{n}) \mathrm{n}-\frac{\tan \mathrm{x}}{\mathrm{x}}\right)=0 \\
& \Rightarrow \mathrm{n}((\mathrm{a}-\mathrm{n}) \mathrm{n}-1)=0 \\
& \Rightarrow(\mathrm{a}-\mathrm{n}) \mathrm{n}=1 \Rightarrow \mathrm{a}=\mathrm{n}+\frac{1}{\mathrm{n}} .
\end{aligned}\)
& \lim _{\mathrm{x} \rightarrow 0} \mathrm{n} \frac{\sin \mathrm{nx}}{\mathrm{nx}} \cdot \lim _{\mathrm{x} \rightarrow 0}\left((\mathrm{a}-\mathrm{n}) \mathrm{n}-\frac{\tan \mathrm{x}}{\mathrm{x}}\right)=0 \\
& \Rightarrow \mathrm{n}((\mathrm{a}-\mathrm{n}) \mathrm{n}-1)=0 \\
& \Rightarrow(\mathrm{a}-\mathrm{n}) \mathrm{n}=1 \Rightarrow \mathrm{a}=\mathrm{n}+\frac{1}{\mathrm{n}} .
\end{aligned}\)
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