Show that $\lim _{x \rightarrow 0} \frac{1}{|x|}=\infty$.
Let $x=0+h$, when $x$ is tends to $0^{+}$
Since x tends to 0, h will also tend to 0.
Right Hand Limit(R.H.L):
$\lim _{x \rightarrow 0^{+}} f(x)$
$=\lim _{x \rightarrow 0^{+}} \frac{1}{|x|}$
$=\lim _{x \rightarrow 0^{+}} \frac{1}{(x)}$
$=\lim _{h \rightarrow 0^{+}} \frac{1}{(0+h)}$
$=\frac{1}{0}$
$=\infty$
Let $x=0-h$, when $x$ is tends to 0 -
ince $x$ tends to $0, \mathrm{~h}$ will also tend to 0 .
Left Hand Limit(L.H.L.):
$\lim _{x \rightarrow 0^{-}} f(x)$
$=\lim _{x \rightarrow 0^{-}} \frac{1}{|x|}$
$=\lim _{x \rightarrow 0^{-}} \frac{1}{(-x)}$
$=\lim _{h \rightarrow 0^{-}} \frac{1}{-(0-h)}$
$=\lim _{h \rightarrow 0^{-}} \frac{1}{h}$
$=\frac{1}{0}$
$=\infty$
Thus,
$\lim _{x \rightarrow 0^{-}} f(x)=\lim _{x \rightarrow 0^{+}} f(x)$
$\therefore \lim _{x \rightarrow 0} \frac{1}{|x|}=\infty$
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