### Home > APCALC > Chapter 10 > Lesson 10.4.1 > Problem10-160

10-160.

Calculate each of the following limits.

1. $\lim\limits _ { x \rightarrow 0 ^ { + } } x ^ { 2 } \operatorname { cot } ( x )$

Rewrite this limit as:

$\lim\limits_{x\to 0^+}\frac{x^2}{\tan(x)}$

Then l'Hôpital's Rule can be used.

1. $\lim\limits _ { x \rightarrow 0 } ( e ^ { x } + x ) ^ { 1 / x }$

Hint: Use natural log.

$L=\lim \limits_{x\to 0}(e^x+x)^{1/x}$

$\ln(L)=\ln\Big(\lim \limits_{x\to 0}(e^x+x)^{1/x}\Big)$

$\ln(L)=\lim \limits_{x\to 0}\frac{1}{x}\ln(e^x+x)=\lim \limits_{x\to 0}\frac{\ln(e^x+x)}{x}$

Now l'Hôpital's Rule can be used.

When the limit is evaluated, the value is $\ln(L)$. Be sure to determine the value of $L$.

1. $\lim\limits _ { x \rightarrow \infty } \frac { e ^ { x } } { x ^ { 2 } }$

Which is the dominant function: $e^x$or $x^2$?

1. $\lim\limits _ { x \rightarrow \infty } \frac { x } { \sqrt { x ^ { 2 } + 1 } }$

What are the dominant terms in the numerator and denominator?