Question
Let $\left| {\mathop {{A_1}}\limits^ \to } \right| = 3$, $\left| {\mathop {{A_2}}\limits^ \to } \right| = 5$ and $\left| {\mathop {{A_1}}\limits^ \to + \mathop {{A_2}}\limits^ \to } \right| = 5$. The
value of $\left( {2\mathop {{A_1}}\limits^ \to + 3\mathop {{A_2}}\limits^ \to } \right)\left( {3\mathop {{A_1}}\limits^ \to - \mathop {2{A_2}}\limits^ \to } \right)$
is :-