Difference between revisions of "Proportion"
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==Direct Proportion== | ==Direct Proportion== | ||
| − | Direct | + | Direct proportion is a proportion in which one number is a multiple of the other. Direct proportion between two numbers '''x''' and '''y''' can be expressed as: <br /> |
<math>y=kx</math><br /> | <math>y=kx</math><br /> | ||
where '''k''' is some [[real number]]. <br /> The graph of a direct proportion is always linear. | where '''k''' is some [[real number]]. <br /> The graph of a direct proportion is always linear. | ||
| Line 11: | Line 11: | ||
<math>xy=k</math><br /> | <math>xy=k</math><br /> | ||
where k is some real number that does not equal zero. <br /> | where k is some real number that does not equal zero. <br /> | ||
| + | |||
| + | ==Exponential Proportion== | ||
Revision as of 19:20, 13 September 2007
| This is an AoPSWiki Word of the Week for Sep 13-19 |
Two numbers are said to be in proportion to each other if some numeric relationship exists between them. There are several types of proportions, each defined by a separate class of function.
Direct Proportion
Direct proportion is a proportion in which one number is a multiple of the other. Direct proportion between two numbers x and y can be expressed as:
where k is some real number.
The graph of a direct proportion is always linear.
Inverse Proportion
Inverse proportion is a proportion in which as one number's absolute value increases, the other's decreases in a directly proportional amount. It can be expressed as:
where k is some real number that does not equal zero.
