The value of 16 sin 44° sin 108° sin 72° sin36° is equal to

We have,

$\begin{array}{l}16\sin {144}^{\circ }\sin {108}^{\circ }\sin {72}^{\circ }\sin {36}^{\circ }\\ =16\sin {36}^{\circ }\cos {18}^{\circ }\cos {18}^{\circ }\sin {36}^{\circ }\\ =16{\cos }^2{18}^{\circ }{\sin }^2{36}^{\circ }=16{\left(\sin {36}^{\circ }\cos {18}^{\circ }\right)}^2\\ =16{\left\{\frac{\sqrt{10-2\sqrt{5}}}{4}\times \frac{\sqrt{10+2\sqrt{5}}}{4}\right\}}^2=5\end{array}$