Date | November 2017 | Marks available | 2 | Reference code | 17N.1.sl.TZ0.4 |
Level | SL only | Paper | 1 | Time zone | TZ0 |
Command term | Complete | Question number | 4 | Adapted from | N/A |
Question
Consider the following propositions.
p: The car is under warrantyq: The car is less than 2 years oldr : The car has been driven more than 20000 km
Write down in words (q∨¬r)⇒p.
Complete the truth table.
State whether the statement ¬p⇒¬(q∨¬r) is the inverse, the converse or the contrapositive of the statement in part (a).
Markscheme
if the car is less than 2 years old or the car has not been driven more than 20000 km, then the car is under warranty (A1)(A1)(A1) (C3)
Note: Award (A1) for if …, then …, (A1) for “or”, (A1) for correct statements in correct order. Accept “If the car has not been driven more than 20000 km or the car is less than 2 years old, then the car is under warranty”. Accept logical equivalent wording for each proposition, eg “less than 20000 km”.
[3 marks]
(A1)(A1)(ft) (C2)
Note: Award (A1) for q∨¬r column correct and (A1)(ft) for (q∨¬r)⇒p column correct. Follow through from their q∨¬r column.
[2 marks]
contrapositive (A1) (C1)
[1 mark]