Ta có:
2006x2005-1/2004x2006+2005 = 2006x(2004+1)-1 / 2004x2006+2005
= 2006x2004 + 2006 -1 / 2004x2006+2005
= 2006x2004+2005 / 2004x2006+2005
= 1
2006*2005-1/2004*2006+2005
2006 * 2005 - 1 / 2004 * 2006 + 2005
2006 × 2005 - 1 / 2004 × 2006 + 2005
2005 * 2006 -1
________________
2006 * 2004 + 2005
2006+2005-1
2004+2006+2005
Tính nhanh
2005×2006-1
2006×2004+2005
2005:2007-1/2004+2005:2006
2006*2005-1/2004*2006+2005 = 1
giai thich va lam vi sao bang 1
2005/2004+2005/2006-2004/2003=??
