Wednesday, October 04, 2006

Introduction to Powers and Roots


Raising a number to a power P means multiplying the number by itself P times.
It is usually denoted with the symbol ^ or **.
 
For example,
        3^0 = 1
        3^1 = 3 = 3
        3^2 = 3*3 = 9
        3^3 = 3 * 3 * 3 = 27
        3^4 = 3 * 3 * 3 * 3 = 81
 
Raising any number to 0 is always defined as 1.
When you use ^2 it is called squaring, and ^3 is calling cubing.
 
 
The opposite function is called finding the root.  It means taking a number n and a root r, and returning the number that, if raised to power r, will give n.  The symbol is hard to show on the computer, so, for a moment, we will just call it rootr().
 
For example,
         root1(3) = 3
         root2(9) = 3
         root3(27) = 3
         root4(81) = 3
 
Now, just like subtraction is adding a negative number, and dividing is multiplying a fraction, roots can be expressed as raising to a fractional power.
 
So,
       3^(1/1) = 3  because 3^1 = 3
       9^(1/2) = 3    because 3^2 = 9
       27^(1/3) = 3  because 3^3 = 27
       81^(1/4) = 3  because 3^4 = 81
      

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