I can complete the truth tables for combinational circuits, but i'm having trouble understanding the concept of flip flops. For exmaple in the diagram i have attached i don't get where are the values for the AND gates on the left & how to construct its truth table.
Thanks for the help.

 

The inputs for the AND gates are coming from the output of the flip flops. You have to assume an initial state on the outputs like A=1 and B=0 and start making the truth table.

 

So it would be like this? Then how do you get the next state due to the flip flops?

A B X
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1

 

Take a look here:

http://www.play-hookey.com/digital/jk_nand_flip-flop.html

This may help you.

Are you sure your circuit is correct, i cant see anything reasonable function with it.