1) Draw the state diagram of a sequential circuit which produces 1 at its output when its last three inputs are equal. For example: to t1 t2 t3 t4 t5 to t7 t8 t9 input x: 0 0 0 0 1 1 1 1 0 1 output y: 0 0 1 1 0 0 1 1 0 0