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Proof by modus ponens

To provep =>q we prove [p A(p =>q)] =>q instead. Example:

We know, that if a right triangle has sides of lengths a, b, c, which c is the largest, then a2 + b2 = c2 {p =łq). Therefore, if we prove that any triangle with sides of lengths x, y, z, where z is the largest, is a right triangle, we may conclude - by modus ponens - that x2 + y2 = z2.