Square Root
2008.03.23
Mathematics

Came across on the web something my dad taught me when I was in 3rd grade that I promptly forgot and "rediscovered" by myself when I was in fifth grade. It is no longer useful in this day and age of calculators. But way back when doing arithmetic in one's head was "cool", it was a great thing to know.

It is certainly nostalgic to think back on that one night when I wrote down my first formal mathematics proof based on nothing but the binomial expansion

(10A + B)2 = 100 A2 + 20 AB + B2

And I went on to right down the algorithm for manually taking the cube root based on

(10A + B)3 = 1000A3 + 300A2B + 30AB2 + B3
and decided that this algorithm is all but impossible to execute by hand, except in exceptional cases.
Posted at 13:29:05 EDT by W comment

© 2004-2008 Willie W. Wong, Sortir en Pantoufles: http://www.math.princeton.edu/~wwong/

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