I have an example where we have an NFA that accepts w and is of the form M1=(Q, Σ, T, s1, F1) and another that accepts wR (the reversal of w) of the form M2=(Q, Σ, T, s2, F2). This is all high level, and theory based, so we don't know what w or the containing language actually is. Now, I need to describe an NFA that accepts w*wR in the same form, M3=(Q, Σ, T, s3, F3), by formally describing each element in the tuple.(adsbygoogle = window.adsbygoogle || []).push({});

I found this old PDF: http://cs.nyu.edu/courses/fall03/V22.0453-001/hw5.pdf where problem 3 looks very similar to my question and provides a solution I don't quite get.

I'm just having trouble describing what M3 would be like. I realize that in order for a string to be accepted, the set pair when finished would need to be the same state, i.e. (q0, q0), but am lost otherwise. Any insight would be appreciated.

**Physics Forums | Science Articles, Homework Help, Discussion**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# NFA for recognizing w*wR

Can you offer guidance or do you also need help?

**Physics Forums | Science Articles, Homework Help, Discussion**