A student claims: *'If , then .'* Which pair is a counterexample?
Answer and explanation
Correct answer: C.
- Step 1: For , , and we have and also (, , , ).
- Step 2: For : but , so it is a counterexample.
Answer
.
Why not the others: The claim fails only when the smaller number has the larger absolute value, which happens only for .
Practise more Counterexamples.
Free questions with an explanation for every one, and full timed TMUA mock tests.
More Counterexamples questions
- A student claims: *'For every positive integer , is prime.'* Which value of is a counterexample?
- A student claims: *'If is a prime number, then is also prime.'* Which value of is a counterexample?
- A student claims: 'If a whole number is divisible by both 4 and 6, then it is divisible by 24.' Which number is a counterexample?
- A student claims: *'If a real number satisfies , then .'* Which value of is a counterexample?
- A student claims: *'If and are irrational numbers, then is irrational.'* Which pair is a counterexample?
- A student claims: *'Every prime number greater than 3 can be written as for some whole number .'* Which prime is a counterexampl…