x.(x + 1) = 2 + 4 + 6 + ... + 2500
x.(x + 1) = (2500 + 2).[(2500 - 2) : 2 + 1] : 2
x.(x + 1) = 2502.1250 : 2
x.(x + 1) = 1250.1251
\(\Rightarrow\) x = 1250
X×(X+1)=2+4+6...2500
x[x+1]=2+4+6+...+2500
x.(x+1)=2+4+6+8+10+...+2500
x.[x+1]=2+4+6+...+2500
x.(x+1)=2+4+6+8+10+.........+2500
Tìm x biết:
x.(x+1) = 2 + 4 + 6 + 8 + 10 +… + 2500
2+4+6+8+...+2500=x.(x+1)
x(x+1)=2+4+6+...+2498+2500 . tìm x
x.(x+1)=2+4+6+....+2500.Tim x
