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Evaluate the following limits : Lim(xto...

Evaluate the following limits :
`Lim_(xto 1) (x^(m)-1)/(x^(n)-1)`

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To evaluate the limit \[ \lim_{x \to 1} \frac{x^m - 1}{x^n - 1}, \] we first observe that substituting \(x = 1\) directly into the expression gives us: \[ \frac{1^m - 1}{1^n - 1} = \frac{0}{0}, \] which is an indeterminate form. Therefore, we can apply L'Hôpital's Rule, which states that if we have a limit of the form \(\frac{0}{0}\) or \(\frac{\infty}{\infty}\), we can differentiate the numerator and denominator separately. ### Step 1: Differentiate the numerator and denominator The numerator is \(f(x) = x^m - 1\) and the denominator is \(g(x) = x^n - 1\). Differentiating both: - The derivative of the numerator \(f'(x) = \frac{d}{dx}(x^m - 1) = mx^{m-1}\). - The derivative of the denominator \(g'(x) = \frac{d}{dx}(x^n - 1) = nx^{n-1}\). ### Step 2: Apply L'Hôpital's Rule Now we can apply L'Hôpital's Rule: \[ \lim_{x \to 1} \frac{x^m - 1}{x^n - 1} = \lim_{x \to 1} \frac{f'(x)}{g'(x)} = \lim_{x \to 1} \frac{mx^{m-1}}{nx^{n-1}}. \] ### Step 3: Substitute \(x = 1\) Now we substitute \(x = 1\): \[ \lim_{x \to 1} \frac{mx^{m-1}}{nx^{n-1}} = \frac{m \cdot 1^{m-1}}{n \cdot 1^{n-1}} = \frac{m}{n}. \] ### Final Result Thus, the limit evaluates to: \[ \lim_{x \to 1} \frac{x^m - 1}{x^n - 1} = \frac{m}{n}. \]
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