(1+1/2) (1+1/3)(1+1/4) x ...x (1+ 1/1999)

Bonjour
1+1/2=3/2
1+1/3=4/3
.
.
1+1/1999=2000/1999

donc
(1+1/2) (1+1/3)(1+1/4) x ...x (1+ 1/1999)=(3/2)*(4/3)*....*1998*1999*1999/2000
=(3*4*.........*1999)/(2*3*4*......*1999*2000)
en simplifiant ça donne 2000/2=1000