Question

Va roogggg ajutați-mă!!!!!
Este urgent!!!! ​

Answer 1

Răspuns:

a) Exemplu: 1+2+3+4+....+100= [100*(100+1)] : 2

(100*101) : 2 = [100*(100+1)] : 2

10100 : 2 = (100*101) : 2

5050=10100:2

5050=5050

B) 1+2+3+....+100 = [100*(100+1)] : 2 = (100*101) : 2= 10100 : 2 = 5050

C) 1+2+3+....+ 99 = [99*(99+1)] : 2 = (99*100) : 2 = 9900 : 2 = 4950