Garfield's proof of the Pythagorean theorem

1876 mathematical proof by the US president

Garfield's proof of the Pythagorean theorem is an original proof the Pythagorean theorem invented by James A. Garfield, the 20th president of the United States. The proof appeared in print in the New-England Journal of Education. At the time of the publication of the proof Garfield was not the President, he was only the Congressman from Ohio. He assumed the office of President on March 4, 1881, and served in that position only for a brief period up to September 19, 1881. Garfield was the only President of the United States to have contributed anything original to mathematics. The proof is nontrivial and, according to the historian of mathematics, William Dunham, "Garfield's is really a very clever proof." The proof appears as the 231st proof in The Pythagorean Proposition, a compendium of 370 different proofs of the Pythagorean theorem.

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