Difference between revisions of "Multiplication"
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*2 times 3 = 3 added two times = 3 + 3 = 6. | *2 times 3 = 3 added two times = 3 + 3 = 6. | ||
2 x 3 = 3 x 2, regardless of the order of the operands. It is said that multiplication is [[commutative]]. | 2 x 3 = 3 x 2, regardless of the order of the operands. It is said that multiplication is [[commutative]]. | ||
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Multiplication is sometimes confusing because the symbol for multiplication is very similar to the letter x; but the letter x can also stand for a variable in algebra, as in "solve for x." | Multiplication is sometimes confusing because the symbol for multiplication is very similar to the letter x; but the letter x can also stand for a variable in algebra, as in "solve for x." | ||
Revision as of 23:56, March 22, 2007
Multiplication is a mathematical operation. Multiplication of positive integers is the same as repeated addition. You multiply two numbers together; that is, multiplication is always performed on two operands. The result is a third number Multiplication is repeated addition. For example:
- 3 times 2 = 2 added three times = 2 + 2 + 2 = 6.
This also works the other way:
- 2 times 3 = 3 added two times = 3 + 3 = 6.
2 x 3 = 3 x 2, regardless of the order of the operands. It is said that multiplication is commutative.
Multiplication is sometimes confusing because the symbol for multiplication is very similar to the letter x; but the letter x can also stand for a variable in algebra, as in "solve for x."
In printed material, slightly different symbols are used for the letter x and the multiplication symbol ×. Sometimes, in mathematics, a centered dot is used to stand for multiplication:
- 3 · 2
- a · b
- 6.022 ·1023
In algebra, quantities may simply be juxtaposed (written next to each other) without any symbols, to indicate multiplication. In this expression, 2ab means 2 times a times b.
- a2 + 2ab + b2