(1+tan π/12)/(1-tan π/12)的值是
问题描述：
(1+tan π/12)/(1-tan π/12)的值是
答
(1+tan π/12)/(1-tan π/12)
=(tanπ/4+tan π/12)/(1-tanπ/4tan π/12)
=tan(π/4+π/12)
=tanπ/3
=√3