ÁD CT $A^{2}=x^{2}+\frac{v^{2}}{\omega ^{2}}$Theo bài ra ta có:$\begin{cases}A^{2}=9+\frac{64}{\omega ^{2}}\\ A^{2}=16+\frac{36}{\omega ^{2}} \end{cases}$
$\Leftrightarrow \begin{cases}A=5(cm) \\ \omega =2(rad/s) \end{cases}$
$\Rightarrow v max=A\omega=10cm/s$