Câu hỏi của phạm thị thu phương

Question

1,Rút gọn phân số

$\frac{-1997.1996+1}{\left(-1995\right).\left(-1997\right)+1996}$

Nguyễn Đắc Định · Accepted Answer

$\dfrac{-1997\cdot1996+1}{\left(-1995\right)\left(-1997\right)+1996}$

$=\dfrac{-1997\cdot1996+1}{1995\cdot1997+1997-1}\ =\dfrac{-1997\cdot1996+1}{1996\cdot1997-1}$

$=\dfrac{-\left(1997\cdot1996-1\right)}{1997\cdot1996-1}\
=-1$Câu trả lời: $\dfrac{-1997\cdot1996+1}{\left(-1995\right)\left(-1997\right)+1996}$

$=\dfrac{-1997\cdot1996+1}{1995\cdot1997+1997-1}\ =\dfrac{-1997\cdot1996+1}{1996\cdot1997-1}$

$=\dfrac{-\left(1997\cdot1996-1\right)}{1997\cdot1996-1}\
=-1$