Question

So sánh A; B; C biết

A = \(\left(-\dfrac{43}{51}\right).\left(-\dfrac{19}{80}\right)\)

B = \(\left(-\dfrac{7}{13}\right).\left(-\dfrac{4}{65}\right).\left(-\dfrac{8}{31}\right)\)

C = \(\dfrac{-5}{10}.\dfrac{-4}{10}.\dfrac{-3}{10}...\dfrac{3}{10}.\dfrac{4}{10}.\dfrac{5}{10}\)

Answer 1

\(A=\left(-\dfrac{43}{51}\right)\left(-\dfrac{19}{80}\right)\)

=>A>0(1)

\(B=\left(-\dfrac{7}{13}\right)\left(-\dfrac{4}{65}\right)\left(-\dfrac{8}{21}\right)\)

=>B<0(2)

C\(=-\dfrac{5}{10}.\left(-\dfrac{4}{10}\right).....\left(\dfrac{4}{10}\right)\left(\dfrac{5}{10}\right)=0\)

=>C=0(3)

Từ 1;2;3 =>A>C>B

Answer 2

\(A=\dfrac{-43}{51}.\dfrac{-19}{80}\Leftrightarrow A>0\left(1\right)\)

\(B=\left(\dfrac{-7}{13}\right).\left(-\dfrac{4}{65}\right).\left(\dfrac{-8}{31}\right)\Leftrightarrow B< 0\left(2\right)\)

\(C=\dfrac{-5}{10}.\dfrac{-4}{10}...........\dfrac{3}{10}.\dfrac{4}{10}.\dfrac{5}{10}\Leftrightarrow C=0\left(3\right)\)

Từ \(\left(1\right)+\left(2\right)+\left(3\right)\Leftrightarrow A>C>B\)