由于（根号2+1)^2=3+2倍根号2
1/根号下3+2倍根号2
=1/根号下(根号2+1)^2
=1/(根号2+1)
=根号2-1
所以
x=log(根号2-1）1/根号下3+2倍根号2
=log(根号2-1）[根号2-1]
=1