Date | May 2009 | Marks available | 2 | Reference code | 09M.1.sl.TZ1.2 |
Level | SL only | Paper | 1 | Time zone | TZ1 |
Command term | Write in words | 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⇒q ;
Write in words the compound proposition
¬p∨q.
The truth table for these compound propositions is given below.
Complete the column for ¬p.
The truth table for these compound propositions is given below.
State the relationship between the compound propositions p⇒q and ¬p∨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.