Question

[nguyen thu ha]

Không quy đồng mẫu số hãy so sánh                   

A = -9 / 10^2011 + -19 / 10^2011 

B = -9 / 10^2011 + -19 / 10^2010

Answer 1

[nghia]

\(A=-\frac{9}{10^{2011}}+\left(-\frac{19}{10^{2011}}\right)\)

\(B=-\frac{9}{10^{2011}}+\left(-\frac{19}{10^{2010}}\right)\)

Do  \(-\frac{9}{10^{2011}}=-\frac{9}{10^{2011}}\)VÀ  \(-\frac{19}{10^{2011}}< -\frac{19}{10^{2010}}\)

\(\Rightarrow-\frac{9}{10^{2011}}+\left(-\frac{19}{10^{2011}}\right)>-\frac{9}{10^{2011}}+\left(-\frac{19}{10^{2010}}\right)\)

\(\Leftrightarrow A>B\)