Question

初一数学题，急急急急急急急急急急急急急急急在线等

已知abc=1，则1+a+ab分之a + 1+b+bc分之b + 1+c+ca分之c

Answer 1

1/(ab+a+1)+1/(bc+b+1)+1/(ac+c+1)
=abc/(ab+a+abc)+1/(bc+b+1)+1/(ac+c+1)······第一项的分子分母的1用abc代替；
=bc/(b+1+bc)+1/(bc+b+1)+1/(ac+c+1)
=(bc+1)/(bc+b+1)+1/(ac+c+1)
=(bc+abc)/(bc+b+abc)+1/(ac+c+1))······第一项的分子分母的1用abc代替；
=(c+ac)/(c+1+ac)+1/(ac+c+1)
=(ac+c+1)/(ac+c+1)
=1

Answer 2

1