I'm having trouble with constructing proof for the following assertions:
R + S = S + R , commutativity
(R + S) + T = R + (S + T)
R (ST) = (RS) T, associativity
(R+S)T = RT + ST, distributivity
Where R,S,T are regular expressions. + is the union operation and when there is no operator it indicates concatenation.
Can anyone give me some guidance?