Four Fours/Lemmata/Three Fours/9

Puzzle

Using exactly $3$ instances of the number $4$, the task is to write an expression for $9$, using whatever arithmetical operations you consider necessary.

Solutions

Solution $1$

$9 = \dfrac {4 - .4} {.4}$

Solution $2$

$9 = \paren {\sqrt {\dfrac 4 {. \dot 4} } }^{\sqrt 4}$

Also see

Previous  ... Next