| Date | May 2009 | Marks available | 1 | Reference code | 09M.1.sl.TZ1.2 |
| Level | SL only | Paper | 1 | Time zone | TZ1 |
| Command term | Complete | Question number | 2 | Adapted from | N/A |
Question
Consider the two propositions p and q.
p: The sun is shining q: I will go swimming
Write in words the compound proposition
\(p \Rightarrow q\) ;
Write in words the compound proposition
\(\neg p \vee q\).
The truth table for these compound propositions is given below.
Complete the column for \( \neg p\).
The truth table for these compound propositions is given below.
State the relationship between the compound propositions \(p \Rightarrow q\) and \(\neg p \vee q\) .
Markscheme
If the sun is shining then I will go swimming. (A1)(A1) (C2)
Note: Award (A1) for “if…then” and (A1) for correct order.
[2 marks]
Either the sun is not shining or I will go swimming. (A1)(A1) (C2)
Note: Award (A1) for both correct statements and (A1) for “either” “…or”.
[2 marks]
(A1) (C1)
[1 mark]
They are (logically) equivalent. (A1) (C1)
Note: Do not accept any other answers.
[1 mark]
Examiners report
The most common error was poor use of the “If...then” connective.
Confusion between “and” and “or” was rare, however, the use of implication in this part was a little too common.
Precise, correct terminology was expected in this part.
