Evaluate LaTeX:  \displaystyle \lim_{x \to \infty} \left(1 + \frac{9}{x}\right)^{\frac{2 x}{7}}

This is an indeterminate form of the type LaTeX:  \displaystyle 1^\infty . Taking the natural logarithm of both sides gives: LaTeX:   \ln(L) = \ln\left( \lim_{x \to \infty} \left(1 + \frac{9}{x}\right)^{\frac{2 x}{7}} \right)  Pulling the limit out of the continuous function and using log properties gives: LaTeX:   \ln(L) = \lim_{x \to \infty}\frac{2 x}{7}\ln\left(1 + \frac{9}{x} \right)  This is an indeterminate form of the type LaTeX:  \displaystyle 0 \cdot \infty . Converting it to type LaTeX:  \displaystyle \frac{0}{0} and using L'Hospitials rule gives: LaTeX:   \ln(L) = \lim_{x \to \infty}\frac{\ln\left(1 + \frac{9}{x}\right)}{\frac{7}{2 x}} = \frac{- \frac{9}{x^{2}}}{- \frac{7}{2 x^{2}}} = \frac{18}{7}  Solving for LaTeX:  \displaystyle L gives LaTeX:  \displaystyle L = e^{\frac{18}{7}}