All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Just Math
2 + 2 = 5 (Posted on 2008-09-16) Difficulty: 3 of 5
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.

See The Solution Submitted by Leming    
Rating: 4.0000 (1 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution A simple modification -- trivial solution | Comment 1 of 5
The ceiling function is the smallest integer greater than or equal to its argument. So

ceil(sqrt((2*2)!)) would work.

Placed into terms of the the floor, or integer, function of greatest integer smaller than or equal to its argument, that same variation is given as


where the square brackets indicate the floor function.

  Posted by Charlie on 2008-09-16 10:48:11
Please log in:
Remember me:
Sign up! | Forgot password

Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (4)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Copyright © 2002 - 2018 by Animus Pactum Consulting. All rights reserved. Privacy Information