Question

Tính nhanh 2007x2006-1/2005×2007+2006

Answer 1

\(\dfrac{2007\times2006-1}{2005\times2007+2006}\)

\(=\dfrac{2007\times2006-1}{\left(2006-1\right)\times2007+2006}\)

\(=\dfrac{2007\times2006-1}{2006\times2007-2007+2006}\)

\(=\dfrac{2007\times2006-1}{2006\times2007-\left(2007-2006\right)}\)

\(=\dfrac{2007\times2006-1}{2007\times2006-1}\)

\(=1\)

Answer 2

\(\dfrac{2007x2006-1}{2005x2007+2006}\)

\(=\dfrac{2007x\left(2005+1\right)-1}{2005x2007+2006}\)

\(=\dfrac{2007x2005+2007-1}{2005x2007+2006}\)

\(=\dfrac{2007x2005+2006}{2005x2007+2006}=1\)

Answer 3

1