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If Lim X → 3 X N − 3 N X − 3 = 108 , Find the Value of N. - Mathematics

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Question

If \[\lim_{x \to 3} \frac{x^n - 3^n}{x - 3} = 108,\]  find the value of n

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Solution

\[\lim_{x \to 3} \left[ \frac{x^n - 3^n}{x - 3} \right] = 108\] 

⇒ x(3)n – 1 = 108
⇒ x(3)n – 1 = 4 × 33

On comparing LHS and RHS, we observe that x is equal to 4. 

\[\begin{array}{c|c|c}2 & 108 \\ 2 & 54 \\ 3 & 27 \\ 3 & 9 \\ 3 & 3 \\& 1\end{array}\]

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Chapter 29: Limits - Exercise 29.5 [Page 33]

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RD Sharma Mathematics [English] Class 11
Chapter 29 Limits
Exercise 29.5 | Q 12 | Page 33

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