Question

S= 1/1×2+1/2×3+1/3×4+...+1/49×50​

Answer 1

Răspuns:

Explicație pas cu pas:

1/1x2 = 1/1 - 1/2

1/2x3 = 1/2 - 1/3

1/3x4 = 1/3 - 1/4

............

1/49x50 = 1/49 - 1/50

__________________

S = 1 - 1/2 + 1/2 - 1/3 + 1/3 - 1/4 + ....+ 1/49 - 1/50

= 1 - 1/50 = 50/50 - 1/50 = 49/50