
72 ◾ Computational Thinking for the Modern Problem Solver
if something is not False then it must be True. e truth table for logical
negation is shown in Figure3.7.
3.2.2.6 Compound Propositions
When we evaluate a proposition, the goal is to determine the truth value
of the proposition. If the proposition involves only a single operator, we
can simply look up one row of a truth table to obtain the answer. Consider
evaluating the proposition
P or Q
for the situation when P = False and Q = True. We can evaluate the value
of “P or Q” by scanning through the disjunctions truth table, nding the
line that corresponds to P = False and Q = Tr