An indirect proof starts with the assumption that the statement we are trying to prove is not true.
An odd number is divisible by 2.
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An indirect proof starts with the assumption that the statement we are trying to prove is not true.
In this case, the statement is that an odd numberis not divisible by 2. The negation of this statement is that an odd number is divisible by 2.
An odd number isdivisible by2.
⇓
An odd number is notdivisible by2.
Finally, we can state the assumption we would make to start the indirect proof.
Assumption:
An odd number is divisible by $2.$
