Question

VRS in exercise 3.e (x <-> (y1 ^ y2)) what does this sign "^" mean?

Comments

Please use tag "VRS" for questions about VRS (that will forward the question to the tutors, otherwise, it may take longer to get an answer).

Answer 1

Short answer: it means exclusive-or.

For the teaching tools, we need some simple writing of the formulas. As you can read on https://es.cs.uni-kl.de/tools/teaching, we use

!,&,^,|,->,<->

for negation, conjunction, exclusive-or, disjunction, implication, and equivalence (with decreasing precedences in this order). 

Alternatively, you may use the characters ¬,∧,⊕,∨,→, and ↔, but you may have hard times to find out how to type these. Yet another alternative would be to write operators in words: not,and,xor,or,imp,eqv (teaching tools accept all the three versions).

Comments

Let me add the following.

Self-Help Tip: If you ever find a logic connective that you don't know, use our teaching tools to generate the truth table. Then you can easily recognize it.

For later in the semester: If you have temporal logic quantifiers that you want to understand, you can form formulas with known quantifiers, and look look at the counterexamples generated by our online tools.