Tiny example
Odd plus odd
Try 3 + 5, 7 + 9 and 11 + 13.
Examples suggest the sum is even. A proof explains why every odd plus every odd is even.
Proof
An argument showing why something must be true.
A proof is more than a convincing example. It explains why a claim has to work, not just why it worked once.
Why it matters
Proof is the heart of mathematical truth. It helps us know the difference between a pattern, a guess and a theorem.
Things to watch for
- Using examples as if they prove every case.
- Not defining what the symbols mean.
- Skipping the step that actually justifies the claim.
Where it connects
proofalgebraic reasoninggeometry
Try it in a tool
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