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Experiment 1: Relation between the sum of any two sides of a triangle and the third side.
| Figure | AB | BC | AC |
AB + BC | BC + AC | AB + AC | Result |
| I. |
— | — | — |
— | — | — |
— |
| II. |
— | — | — |
— | — | — |
— |
Conclusion: The sum of any two sides of a triangle is greater than the third side.
i.e., AB + BC > AC, BC + AC > AB, and AB + AC > BC.
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Experiment 2: The angle opposite the longer side is greater than the angle opposite the shorter side.
| Figure | AB | ∠ACB | BC |
∠BAC | AC | ∠ABC | Result |
| I. |
— | — |
— | — |
— | — |
— |
| II. |
— | — |
— | — |
— | — |
— |
| III. |
— | — |
— | — |
— | — |
— |
Conclusion: The angle opposite to the longer side is greater than the angle opposite to the shorter side.