At a glance
6
Occurrences
questions
5
Years
5
Papers
6
Worked
100%
When this method shows up
Years in which at least one question on this paper triggers the method.
Other top methods in Logic & Proof
- To find the first wrong line of a purported proof, scan for the classic order-breaking operations×7
- To disprove a 'for all' claim, build a single counterexample that obeys the hypothesis but breaks the conclusion×7
- Treat 'necessary' and 'sufficient' as two separate one-way tests, and break whichever direction can fail×7
- For a 'which of I, II, III must be true' item, confirm the forced ones then kill each survivor with one targeted counterexample×6
- Mind the direction of an implication: the contrapositive keeps the truth value, the converse and inverse do not×6
See the worked examples
Open this method in the 3-panel methods app to see the demonstration, every linked past-paper question, and how to attack it.
Open method in the TMUA appTry a method on a real paper
Open the TMUA methods app to see worked examples, linked questions and the 3-panel revision view.
Open TMUA methods