(1 / 2)^(- 2) - 丨2√2 - 3丨+ √(3 / 8)
= 2 ² + (2√2 - 3)+ √3 / 2√2
= 4 + 2√2 - 3 + √6 / 4
= 1 + 2√2 + √6 / 4