R1 implies R2 if all the truth table rows that makes R1 true makes R2 also 
true. for example, Relation 2 implies Relation 6.

(R1&R2)==R1
& is the bitwise and. R1&R2 is true for the rows that both R1 and R2 are true. If that is R2, then that means that whatever makes R1 true also makes R2 true.