Nevertheless, to answer your question:
- Look for the lines of the table where the output value is 1 (True)
- For each of these lines, construct a logical expression, using AND and NOT as appropriate, to construct the expression that corresponds to the True-False values of the input variables. (See below for examples.)
- Combine each of these expressions using OR's to give a single Boolean expression to represent the output of the complete table.
- If desired (and if you can!), simplify the resulting Boolean expression.
In the (part-)example that you quote, on lines 2, 3 and 4.
On line 2, and are True; is False. So this line is AND AND (NOT ); or
On line 3, is True; is False; is True. So this line is
Similarly line 4 is
Combining these three expressions using OR's then, we get:
(This could then be simplified to , if your Boolean algebra is up to it.)