A rectangle of numbers

Six numerals and two ? symbols are arranged in a $2\times4$ rectangle.

? ?
8 9
5 6
2 3


Apparently, either one or two different symbols are needed to replace the two ? symbols. What are they?

• You went to the trouble of making an account, so why not log back on and accept an answer? Even if you don't know by now, you can adopt the puzzle as your own and settle on one. – can-ned_food Mar 22 '17 at 1:48

My guess would be:

/ and *

Why?

Look at the numeric keypad on your keyboard. Above 8 there is a slash (/) and above 9 there is an asterisk (*)

• Or the number strip, then you get *, and (. – Travis Feb 26 '15 at 18:54

The grid of numbers is

?  ?
8  9
5  6
2  3


Each number is three greater than the number below it and one greater than the number to its left (if there is one). Alternatively, think of each column as an arithmetic progression $2,5,8,?$ and $3,6,9,?$ (or reversed).

So, the missing numbers are 11 and 12.

11 12
8  9
5  6
2  3

• could also be 11 mod 10 and 12 mod 10 – dmg Feb 25 '15 at 8:24
• that's too obvious to be true – Novarg Feb 25 '15 at 8:58

It's 11 and 12 like the answer above mine but the reasoning could also be

2+3 = 5 + 6 = 11 (written as sum of two consecutive numbers 5 and 6) : 8+9 = 17 + 6 = 23 (11 + 12)