Here is a wonderful small teaser I got from the site brilliant.org. I have seen at least two solutions to this puzzle, so try your creativity, there might be more.
Look at the equation
1 4 9 = 16
Add any mathematical operators in the above equation to balance the two sides, with the following exceptions:
- Cannot use “not equal to” sign
- Cannot use any operator that requires you to use a digit
As always, please send your answers as comments within the blog (preferred), or send an e-mail to alokgoyal_2001@yahoo.com. Please do share the puzzle with others if you like, and please also send puzzles that you have come across that you think I can share in this blog.
Happy New Year!
Alok Goyal's Puzzles Page 
Couldn’t resist when I saw this on LinkedIn and instantly thought of a possible answer!
4! + 1 – 9 = 16
Happy New Year!
-1+√4+√9=√16
Here’s another one
-1+√4+√9=√16
Very creative though technically not allowed
Sent from Yahoo Mail on Android
Alok – I looked at 16 as 8*2 and 4*4 and thus came up with two ways of representing the LHS as these. Solution one will be (9-1)*(4)^0.5 solution 2 will be 4*(1+(9)^0.5).
Prakhar, the order of the digits cannot be changed
Alok – two solutions which I thought of were (9-1)*4^0.5 and 4*(1+9^0.5)
Alok – another solution might be
4 – ((9)^0.5 – 1 ) = 16^0.25
1 + 4! – 9 = 16
-1 – 4^3 + 9^2 = 16
Arunabh, you have used operators that require additional numerals and hence this will not work
-1-4+9=root16
-5+9=4
(1+4)squ-9=16 alok goyal………..aloknmh@gmail.com
25-9=16
(1+4)square-9=16
25-9=16
this one does not work as you need to use “power of 2” which will require you to use a numeral
-1-4+9=root 16
-5+9=4
1+4!-9=16
This works if you consider << as an operator.
1<<4%9 = 16
I did not understand this one, what does << do?
shifts bits to the right in some programming languages 🙂