To prove that √2 is an irrational number, a teacher begins by assuming that it…
2019
To prove that √2 is an irrational number, a teacher begins by assuming that it is a rational number and then proceeds to show how this assumption is not feasible. This is an example of proof by
- A.
Induction
- B.
Deduction
- C.
Contradiction
- D.
Verification
Attempted by 169 students.
Show answer & explanation
Correct answer: C
In proof by contradiction, we begin by assuming the opposite of what we want to prove and then show that this assumption leads to an impossibility or contradiction. Here, the teacher assumes √2 is rational and then shows that this assumption is not feasible, so the method is proof by contradiction.