Answer
The multiplication of the complex numbers in the polar form is $30\left( \cos 70{}^\circ +i\sin 70{}^\circ \right)$.
Work Step by Step
Here,
$\begin{align}
& {{z}_{1}}=6\left( \cos 20{}^\circ +i\sin 20{}^\circ \right) \\
& {{z}_{2}}=5\left( \cos 50{}^\circ +i\sin 50{}^\circ \right) \\
\end{align}$
Therefore,
$\begin{align}
& {{z}_{1}}\times {{z}_{2}}=6\times 5\left( \cos \left( 20{}^\circ +50{}^\circ \right)+i\sin \left( 20{}^\circ +50{}^\circ \right) \right) \\
& =30\left( \cos 70{}^\circ +i\sin 70{}^\circ \right)
\end{align}$
The multiplication of the complex numbers in the polar form is $30\left( \cos 70{}^\circ +i\sin 70{}^\circ \right)$
