please empty your brain below

Just one expression each, thanks.
Simplest expression wins :)

Here are some operations you can cut and paste: +-×÷()√!

Also "point four" is fine, that's ·4
and "point four recurring" can be ·4·
1=(4+4)/(4+4)
No, just two fours.
(Embarrassed look)

1=4/4
8 = 4+4
6 = 4! / 4
6 = 4 + √4
4=√(4×4)
4-4=0
2 = 4 / √4.

Regards
7 =⌈√44⌉

dg writes: Not equal.
⌊4 - log(4)⌋ = 3
(those truncated square brackets are ceiling/floor functions that round up and down, so yes, I'd argue this is equal)
I'm not accepting ceiling/floor functions (except maybe as an absolute last resort).
Log 4 (to base 4) = 10
[OK - I admit this isn't actually the number ten but it looks like it]
I'm not accepting different number bases either :)
You're accepting "to the power of 0.5" (ie square root), does this mean that we can use to the power of any number we like? Eg four squared, four cubed, four to the power of zero?

Thanks
Those use other digits (2, 3 & 0), so no.
10 = 4/·4
Just in case you end up accepting them as an absolute last resort:

9 = ⌊4! × ·4⌋
The original Four Fours problem doesn't allow ⌊ ⌋ and ⌈ ⌉ because it's too easy that way... it's not proper arithmetic.
how about 9 = 4 / ·4·
See, not necessary :)
<snip>
does "just one expression each" mean one per question, or one per participant... because i have one more ;-)
That's your lot, thanks.
Ah-ha!

5 = √4 / ·4
Now that we've seen the solution for 9, 3 is easy:

3 = sqrt( 4 / ·4· )
3 = Γ4 / √4

Where Γ is the gamma function and

Γ(4) = (4− 1)! = 6
The simpler version wins :)
Haha, yes that was over complicated…

How about:

7 = !4 - √4
I don't think the wider public are ready for subfactorials.
So that's...

  0 = 4 - 4
  1 = 4 ÷ 4
  2 = 4 ÷ √4
  3 = √(4 ÷ ·4·)
  4 = √4 + √4
  5 = √4 ÷ ·4
  6 = 4 + √4
  ...
  8 = 4 + 4
  9 = 4 ÷ ·4·
10 = 4 ÷ ·4

...and 7 remains complicated stuff
7 = [(4^3 - 4^2 - 4^2) - 4] / 4
Sorry, what do those dots in the expressions for 9 and 10 mean?
No, two 4s.
That's five 4s, two 2s and a 3.
·4  = 0.4
·4· = 0.44444444444...
7 = ceiling ( sqrt 44 )

Cheating, of course, but close!
Someone’s already tried that.
7 = Perfect(√4 ) / 4
Strayed a very long way from "common mathematical symbols" there...
7=4+4-(4/4)
No, two fours.
7 = (4! / 4)++
I would note, without offering an expression, that 7 happens to be the fourth prime number.










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