I don't know what 55² is, and I wouldn't bother to compute it by hand.
But I do know:
a²-b² = (a-b)(a+b)
a² = (a-b)(a+b)+b²
Setting a=55 and b=5 we get
55² = (55-5)(55+5) + 5²
Suddenly it's obvious, not because of the numbers, but because of the structure.
The facility with numbers is an epiphenomenon.
2/n, n=2
Colin the Mathmo /
npub1tn…j5nzk
2024-09-09 13:16:50
Author Public Key
npub1tnfy2kgy52nayvryzxr7w7aa8r88jp43prhtdazwydv097exa7ms8j5nzkPublished at
2024-09-09 13:16:50Event JSON
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"content": "I don't know what 55² is, and I wouldn't bother to compute it by hand.\n\nBut I do know:\n\na²-b² = (a-b)(a+b)\n\na² = (a-b)(a+b)+b²\n\nSetting a=55 and b=5 we get\n\n55² = (55-5)(55+5) + 5²\n\nSuddenly it's obvious, not because of the numbers, but because of the structure.\n\nThe facility with numbers is an epiphenomenon.\n\n2/n, n=2",
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