Solution:

The given sequential logic diagram

A buffer component is used at input of $A$

flip flop

The state equations are

$D_A=Q_{A}x$

$D_B=Q_{A}o+Q_B$ where $o+exoR$

Let present state equations be

$D_A=Q_A$ and $D_B=Q_{Bn}$

Then next state equations can be written as

$Q_{A(n+1)}=Q_{An}$&$Q_{B(n+1)}=Q_{An}o+Q_{Bn}$