Final answer:
Proofs by contradiction are a logical method used in mathematics and logic to prove propositions by assuming the opposite and showing it leads to a contradiction.
Step-by-step explanation:
Proofs by contradiction are a logical method used in mathematics and logic. They involve assuming the opposite of what we want to prove and then showing that it leads to a contradiction.
If a contradiction is reached, it means the opposite assumption must be false, and therefore the original proposition is true.
For example, to prove that the square root of 2 is irrational, we assume the opposite (that it is rational) and show that it leads to a contradiction.