= 2006 x ( 2005 + 2 ) - 1997 / 2006 x 2005 + 2015
= 2006 x 2005 + 2006 x 2 -1997 / 2006 x 2005 + 2015
= 2006 x 2005 + 4012 - 1997 / 2006 x 2005 + 2015
= 2006 x 2015 + 2015 / 2006 x 2005 + 2015
= 1
Nhớ k nha
\(\frac{2006\times2007-1997}{2006\times2005+2015}=\frac{2006\times\left(2005+2\right)-1997}{2006\times2005+2015}\)
\(=\frac{2006\times2005+2006\times2-1997}{2006\times2005+2015}\)
\(=\frac{2006\times2005+4012-1997}{2006\times2005+2015}=\frac{2006\times2005+2015}{2006\times2005+2015}=1\)
2006 X 2017 - 1997 / 2006x2005+2015 = 2017-1997 / 2005 +2015 = 10 / 4020 = 1 /402
