\(A=\frac{4047991-2010.2009}{4050000-2011.2009}=\frac{4047991-2010.2009}{4050000-\left(2010+1\right).2009}=\frac{4047991-2010.2009}{4050000-\left(2010.2009+1.2009\right)}\)
\(=\frac{4047991-1}{4050000-\left(1+2009\right)}=\frac{4047990}{4050000-2010}=\frac{4047990}{4047990}=1\)