summing exponents


Posted by Tom Carlson on September 07, 2000 9:42 AM

In math, when you are using a summation symbol you want to sum an equation like, (1+x)^n, where n varies from 1 to 60. How can you do this in Excel? I have tried the SUM function in various ways but it hasn't worked. Thanks a lot.



Posted by Celia on September 07, 0100 8:58 PM


Tom
If you mean that you want to sum the result of the formula (1+x)^n for various values of n, then if the value of x is in cell A1 and the n values are in B1:B10 :-

=SUM((1+A1)^(B1:B10))

This is an array formula, so it must be entered with Ctrl+Shift+Enter.
If entered by pressing Enter only, it will display the result based only on the first value of n (I.E. it will display the result of =(1+A1)^B1

Celia