tính nhanh 1995 x 1996-1000 ____________________________ 1995 x 1995+995

Hướng dẫn trả lời:

$\text{$\dfrac{1995 × 1996 – 1000}{1995 × 1995 + 995}$.}$

$\text{= $\dfrac{1995 × (1995 + 1) – 1000}{1995 × 1995 + 995}$.}$

$\text{= $\dfrac{1995 × 1995 + 1995 – 1000}{1995 × 1995 + 995}$.}$

$\text{= $\dfrac{1995 × 1995 + 995}{1995 × 1995 + 995}$.}$

$\text{= 1.}$

Đáp án:

$\text{= 1.}$