Mình sửa lại chút.
\(\dfrac{1}{99.97}-\dfrac{1}{97.95}-\dfrac{1}{95.93}-\dfrac{1}{5.3}-\dfrac{1}{3.1}\)
\(=\dfrac{1}{99.97}-\left\{\dfrac{1}{97.95}+\dfrac{1}{95.93}\right\}-\left\{\dfrac{1}{5.3}+\dfrac{1}{3.1}\right\}\)
\(=\dfrac{1}{99.97}-\dfrac{1}{95}.\left\{\dfrac{1}{97}+\dfrac{1}{93}\right\}-\dfrac{1}{3}.\left\{\dfrac{1}{5}+\dfrac{1}{1}\right\}\)
\(=\dfrac{1}{99.97}-\dfrac{1}{95}.\dfrac{190}{97.93}-\dfrac{1}{3}.\dfrac{6}{5}\)
\(=\dfrac{1}{99.97}-\dfrac{2}{97.93}-\dfrac{6}{15}\)
\(=\dfrac{1}{97}.\left\{\dfrac{1}{99}-\dfrac{2}{93}\right\}-\dfrac{2}{5}\)
\(=\dfrac{-35}{297693}-\dfrac{2}{5}\)
\(=\dfrac{-175-595386}{1488465}\)
\(=\dfrac{-595561}{1488465}\)
Tách ra và rút gọn là xong bạn nhé !!
\(\dfrac{1}{99.97}-\dfrac{1}{97.95}-\dfrac{1}{95.93}-\dfrac{1}{5.3}-\dfrac{1}{3.1}\)
\(=\dfrac{1}{97.93}\left\{\dfrac{1}{97.95}+\dfrac{1}{95.93}\right\}-\left\{\dfrac{1}{5.3}+\dfrac{1}{3.1}\right\}\)
\(=\dfrac{1}{99.97}-\dfrac{1}{95}-\left\{\dfrac{1}{97}+\dfrac{1}{93}\right\}-\dfrac{1}{3}-\left\{\dfrac{1}{5}+\dfrac{1}{1}\right\}\)
\(=\dfrac{1}{99.97}-\dfrac{1}{95}.\dfrac{190}{97.93}-\dfrac{1}{3}.\dfrac{6}{5}\)
\(=\dfrac{1}{99.97}-\dfrac{2}{97.93}-\dfrac{6}{5}\)
\(=\dfrac{1}{97}.\left\{\dfrac{1}{99}-\dfrac{2}{93}\right\}-\dfrac{2}{5}\)
\(\dfrac{-35}{297643}-\dfrac{2}{5}=\dfrac{-175-595386}{1488465}\)
\(=\dfrac{-595561}{1488465}\)
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