How is it possible calculate the following limits?
$\displaystyle \lim_{x\to 0} \frac{\arctan x -x}{x^3}$
$\displaystyle \lim_{x\to 0} \frac{\ln(1+x)-x}{x^2}$
$\displaystyle \lim_{x\to 0} \frac{\sinh x -x}{x^3}$
$\displaystyle \lim_{x\to 0} \frac{\cosh x -1}{x^2}$
I have calculated them using L'Hospital's rule.
For example:
$\displaystyle \lim_{x\to 0} \frac{\cosh x -1}{x^2}=$
$\displaystyle =\lim_{x\to 0} \frac{\sinh x}{2x}=$
$\displaystyle =\lim_{x\to 0} \frac{\cosh x}{2}=$
$=\displaystyle \frac{1}{2}$
But how is it possible to calculate them without using L'Hospital's rule nor Maclaurin series?