A cura di: Francesco Speciale

Svolgimento:
$(sqrt5-1)/(sqrt(5-sqrt5))*sqrt((5-sqrt(15))/(10))*sqrt((15)/2)=$
$=(sqrt5-1)*(sqrt(1/(5-sqrt5)*(5-sqrt5)/(10)*(15)/2))=$
$=(sqrt5-1)*sqrt(3/4)=(sqrt5-1)*sqrt3/2=(sqrt(15)-sqrt3)/2$.