由原式得分母：1{6/1{4/1x{2/x-1+3}+5}+7}=8
6/1{4/1x{2/x-1+3}+5}+7=8 6/1{4/1x{2/x-1+3}+5=1
1{4/1x{2/x-1+3}+5=6 4/1x{2/x-1+3}=1
2/x-1+3=4 2/x-1=1
x-1=2 x=3