1/x＋1/y=1*(1/x＋1/y)==(2x＋3y)*(1/x＋1/y)==2+2*x/y+3*y/x+3=5+2*x/y+3*y/x==________________ __5+2*x/y+3*y/x>=5+2√(2*x/y)*(3*y/x) ==5+2√6当且仅当3y/x=2x/y时,取“=” ._________________________________...