Question

найдите выражения 19разделить на 20/21-21/22

Answer 1

$displaystyle dfrac{19}{frac{20}{21} ^{(22} -frac{21}{22} ^{(21} } = dfrac{19}{frac{20cdot 22-21cdot 21}{21cdot 22}} =\\\=19cdot dfrac{(20+1)cdot 22}{20cdot 22-(20+1)cdot 21} =\\\=19cdot dfrac{20cdot 22+22}{20cdot 22-(20cdot 21+21)} =\\\=19cdot dfrac{440+22}{20cdot (22-21)-21} =\\\=19cdot dfrac{462}{20-21} =\\\=(20-1)cdot (-462)=-(9240-462)=\\=-(9000-222)=bold{-8778}$