Variables and constants Algebra
Posted by
Ravi Kumar at Wednesday, December 23, 2009
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In arithmetic, the numbers used have definite values. These values do not change. But the letters used in algebra have no particular value and may have any value assigned to them.
Consider,
The perimeter 'p' of a rectangle of length 'l' and breadth 'b' is p = 2(l+b). Here '2' is a fixed number. The letters p, l and b have no fixed value. They can take any positive value depending upon the size of the rectangle.
So, a letter symbol which can take any value of a certain set is called a variable. Above p, l and b are variables.
Quantities which have only one fixed value are called constants. Above 2 is a constant.