Represent 4 with four identical digits using only the usual arithmetic operations, factorials and square roots

Solution

1 + 1 + 1 + 1 = 4
2×2 + 2 - 2 = 4
√3×√3 + 3/3 = 4
√4×√4 + 4 - 4 = 4
5 - √5×√5/5 = 4
6 - (6 + 6)/6 = 4
77/7 - 7 = 4
√√(8 + 8) + √√(8 + 8)= 4
√√9×√√9 + 9/9 = 4
0! + 0! + 0! + 0! = 4


Related material
Read more...

  • Funny Arithmetic
  • A single formula to express all numbers
  • Any Integer with Three 2s
  • Representation of numbers with a single 4. The rules and the possibilities
  • One 4, a story
  • Three 3's
  • Representation of numbers with three 4's
  • Representation of numbers with three 5's
  • Representation of numbers with four 3's
  • Representation of numbers with four 4's
  • Representation of numbers with four 5's
  • A problem of representing 6 by three identical digits
  • A 9's Fan's Clock
  • Make an Identity
  • Fun with numbers: place plus/minus signs between the digits
  • 24 with One Digit
  • Representation of 3 with Three Equal Digits

    • |Contact| |Front page| |Contents| |Algebra|

     

    Copyright © 1996-2018-1996-2001 Alexander Bogomolny

    72099781