Cho A=1/1.2 + 1/3.4 +....+ 1/999.1000 B=1/501.1000 + 1/502.999 +......+ 1/999.502 + 1/1000.501 Tính A/B TRẢ LỜI NHANH VÀ HAY SẼ ĐƯỢC CÂU TRL HAY NHẤT NHÉ ĐÚNG THÔI CŨNG ĐƯỢC :)))))))))

$\text{A = $\frac{1}{1.2}$ + $\frac{1}{2.3}$ + $\frac{1}{3.4}$ + ... + $\frac{1}{999.1000}$ }$

$\text{A = $\frac{1}{1}$ - $\frac{1}{2}$ + $\frac{1}{2}$ - $\frac{1}{3}$ + $\frac{1}{3}$ - $\frac{1}{4}$ + ... + $\frac{1}{999}$ - $\frac{1}{1000}$ )}$

$\text{A = $\frac{1}{1}$ - $\frac{1}{1000}$}$

$\text{A = $\frac{999}{1000}$}$

$\text{B = $\frac{1}{501.1000}$ + $\frac{1}{502.999}$ + ... + $\frac{1}{999.502}$ + $\frac{1}{1000.501}$ }$

$\text{B = $\frac{1}{499}$ . ( $\frac{499}{501.1000}$ + $\frac{499}{502.999}$ + ... + $\frac{499}{999.502}$ + $\frac{499}{1000.501}$ )}$

$\text{B = $\frac{1}{499}$ . ( $\frac{1}{501}$ - $\frac{1}{1000}$ + $\frac{1}{502}$ - $\frac{1}{999}$ + ... + $\frac{1}{999}$ - $\frac{1}{502}$ + $\frac{1}{1000}$ - $\frac{1}{501}$ )}$

$\text{B = $\frac{1}{499}$ . 0}$

$\text{B =                 0}$