2 + 2/3 +2/6 + 2/12+ .............+ 2/x(x + 1)= 3980/1991
1/3+1/6+1/10+...+2/x(x+1)=1999/2000. ; b)2+2/3+2/6+2/12+...+2/x(x+1)=3980/1991
Giup toi giai bai toan:
1+2/6+2/12+.....+2/x(x+1)=3980/1991
1+1/3+1/6+1/10+...+2/x.(x+1)=3980/1991
2+ 2/3+2/6+2/12+...+2/x(x+1)= 1 1989/ 1991
tìm x biết :
2+2/3+2/6+2/12+....+2/x*(x+1) = 1+1989/1991
2 + 2/3 + 2/6 + 2/12 +...+ 2/x.(x+1) = 1+1989/1991
Giải đầy đủ hộ mình nhé!
2 + 2/3 + 2/6 + 2/12 +...+ 2/x.(x+1) = 1+1989/1991
Giải đầy đủ hộ mình nhé!
tim x
2+2/3+2/6+2/12+...+2/x*(x+1)=1+1989/1991
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