Question

（2011的3次方-2011的2次方-2010）分之2011的3次方-2乘2011的2次方-2009

Answer 1

(2011^3 - 2 * 2011^2 -2009) = 2011^2 *(2011-2) -2009 = (2011^2 -1) * 2009

(2011^3 - 2011^2 - 2010) = 2011^2 *( 2011-1) - 2010 = (2011^2 -1) * 2010

(2011^3 - 2 * 2011^2 -2009) / (2011^3 - 2011^2 -2010)

= 2009 / 2010