Monday, 12 January 2015

calculus - Using L'Hôpital's rule

Using L'Hôpital's rule to find
$$\lim_{x\to \infty} \left(\frac {\tan\beta x - \beta \tan x} {\sin\beta x - \beta \sin x}\right)$$
Where $\beta$ is a nonzero constant different from $\pm 1$.



I find this question weird because the limit does not confine to one of the forms that you can use L'Hôpital's rule. It is not one of the following form $\infty \over \infty$, $0 \over 0$, $\infty -\infty$, $0\times \infty$, $1^\infty$, $\infty^0$. So we cannot directly use the rule. How do I justify this question?

No comments:

Post a Comment

real analysis - How to find $lim_{hrightarrow 0}frac{sin(ha)}{h}$

How to find $\lim_{h\rightarrow 0}\frac{\sin(ha)}{h}$ without lhopital rule? I know when I use lhopital I easy get $$ \lim_{h\rightarrow 0}...