Using only two 2s and any of the standard mathematical symbols, write an expression whose value is equal to 5.

An approach could be: sqrt((2 * 2)!) = 4.90

Standard mathematical symbols (for this problem) are: addition, subtraction, multiplication, division, exponentiation, square root, factorization, parenthesis, positive, negative, ln, log. Superfactorials and such are not excluded, but not part of the desired solution. Any symbol having a value of its own, such as e, pi, and infinity, is not authorized.

2 + 2 + x/x : x not = (x - x)

2 + 2 + x(x - x) : x not = (x - x)

(Sorry for the grammatical error in the message title. Should be "Do these count?". It is an example of what happens when one changes a singular to a plural in the middle of typing, then fails to edit before submitting.) 

Edited on September 17, 2008, 1:30 am

Posted by Dej Mar on 2008-09-17 00:56:15