Left Hand Side,
$\left(\frac{a^{l}}{a^{m}}\right)^{n}\cdot\left(\frac{a^{m}}{a^{n}}\right)^{l}\cdot\left(\frac{a^{n}}{a^{l}}\right)^{m}$
$=\frac{a^{ln}}{a^{mn}}\cdot\frac{a^{lm}}{a^{ln}}\cdot\frac{a^{mn}}{a^{lm}}^{}$
$=a^{ln-mn}\cdot a^{lm-ln}\cdot a^{mn-lm}$
$=a^{ln-mn+lm-ln+mn-lm}$
$=a^0$
$=1$
$=$ Right Hand Side [Proved]