\(\frac{1978.1979+1980.21+1958}{1980.1979-1978.1979}\)
= \(\frac{1978.1979+1979.21+21+1958}{1979.\left(1980-1978\right)}\)
= \(\frac{1978.1979+1979.21+1979}{1979.2}\)
= \(\frac{1979.\left(1978+21+1\right)}{1979.2}\)
= \(\frac{1978+21+1}{2}\)
= \(\frac{2000}{2}\)= 1000
=1979x1978+1979x21+21+1958/1979x(1980-1978)
=1979x1979+1979/1979x2
=1979x1980/1979x2
=1979x2x990/1979x2
=990 chúc bạn học tốt nha
=1979x1978+1979x21+21+1958/1979x(1980-1978)
=1979x1979+1979/1979x2
=1979x1980/1979x2
=1979x2x990/1979x2
=990
