Hello everyone i'm not sure if i'm understanidng this relation. The question is: Let S be the set of all strings in a's and b's. Define a relation T on S as folows: FOr all s, t in S, s T t if and only if t = as. That is, t is the concatenation of a with s. c. Is ba T aba? I said yes, because aba is the concatneation of a with ba. Thus a + (ba) e. Is abb T^-1 bba? Well I know this means, (abb T^-1 bba) if and only if (bba T abb) now abb, can be broken into a + bb, but would that break the rules? like the order odes it have to be the same? So for this one i would say no. f. Is abba T^-1 bba? this means bba T abba I would say yes, becuase abba is just a + bba Any clarification if i'm understanding right? Thanks!