Suppose I have a language L = {wxwR} where wR is the reverse of w, w and x has minimum length of 1, w can consist of either 0's or 1's, while x can only consist of 1's.
How do I prove that this language is not regular? Is there any other way than using the pumping lemma? If using the pumping lemma, I'm still figuring out what x,y, and z I should pick for the string s=xyz, I would appreciate if you give me any hint.
Thanks!