m (Multiplication)
m (Multiplication)
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The action of repeated [[addition]]s: $a\times b=\underbrace{a+a+\cdots+a}_{\hbox{$b$ times}}$.
 
The action of repeated [[addition]]s: $a\times b=\underbrace{a+a+\cdots+a}_{\hbox{$b$ times}}$.
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By looking at it from a geometric point of view, it is not difficult—although not trivial either—to see that $a\times b=b\times a$.
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An interesting problem regards the complexity, or cost of multiplication. In 1960, Karatsuba improved on the "school method".
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== Links ==
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* [http://www.ccas.ru/personal/karatsuba/divcen.pdf Karatsuba recollections and comments on his methods].

Revision as of 05:11, 27 March 2020

Multiplication

The action of repeated additions: $a\times b=\underbrace{a+a+\cdots+a}_{\hbox{$b$ times}}$.

By looking at it from a geometric point of view, it is not difficult—although not trivial either—to see that $a\times b=b\times a$.

An interesting problem regards the complexity, or cost of multiplication. In 1960, Karatsuba improved on the "school method".

Links