Question

a= 1/2+1/3+....+1/11 b= 3/2 +4/3+...+12/11
Numarul b-a are valoarea ?

Answer 1

Răspuns:

Explicație pas cu pas:

a= 1/2+1/3+....+1/11

b= 3/2 +4/3+...+12/11

b-a = (3/2 +4/3+...+12/11) - (1/2+1/3+....+1/11) =

(3/2-1/2) + (4/3-1/3) + .....+(12/11-1/11) =

= (2/2+3/3+....+11/11) =  1+1+....1 de 10 ori = 10

Answer 2

Răspuns:

-1/2+3/2=2/2=1 ;-1/3+4/3=3/3=1,..., -1/11+12/11=11/11=-=1; (1)×10=10

Explicație pas cu pas: