Tutorial for Week 2 Material
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1. Consider the following statement:

  (S1) Every class has a constructor.

What would be an appropriate domain/universe for (S1)?

Rewrite (S1) using the precise symbolic notation.

2. Consider the following statement:

  (S2)  If a program does not compile, then it has errors.

a) Rewrite (S2) using precise symbolic notation.

b) Suppose claim (S2) is true.  
What conclusions can be reached, if we know:

A program does not compile

A program does compile

A program has errors

A program does not have errors

c) In English, write the contrapositive of (S2).

Suppose (S3) is true.  
What conclusions can be reached, if we know:

A program does not compile

A program does compile

A program has errors

A program does not have errors

d) In English, write the converse of (S2).

Suppose (S4) is true.
What conclusions can be reached, if we know:

A program does not compile

A program does compile

A program has errors

A program does not have errors

3. Let P, Q and R be sentences. Make a Venn diagram with three intersecting
   sets, one each for situations that P/Q/R are true.

  Consider the following form you've probably seen in your textbooks:

    (1) Suppose P. Then Q implies R.

  Shade in the regions corresponding to situations consistent with (1),
  and cross out the regions that are inconsistent with (1).