Ximpledu

Indirect Proof

See how to prove a statement
by using indirect proof.
1 example and its solution.

Indirect Proof

Definition

StatementReason
~ProveAssumption
ProveContradiction
Indirect proof (proof by contradiction)
is another way to prove a statement.
Instead of proving a statement directly,
you show a contradiction
to prove a statement indirectly.

How to:
Assume that ~prove is true.
Then show a contradiction.
This is made by the wrong assumption:
~Prove.
→ ~Prove: ( x )
→ Prove: ( o )

Logic (Geometry)
Two-Column Proof

Example

Given: AM ≠ MB
Prove: M is not the midpoint of AB

Solution