x≠kπ+π/2
1+2sinx≠0 sinx≠-1/2
x≠2kπ-π/2±π/3
tanx=2tan(x/2)/(1-tan^2(x/2))
sinx=2tan(x/2)/(1+tan^2(x/2))
y=5tanx/1+2sinx求函数的定义域和值域
x≠kπ+π/2
1+2sinx≠0 sinx≠-1/2
x≠2kπ-π/2±π/3
tanx=2tan(x/2)/(1-tan^2(x/2))
sinx=2tan(x/2)/(1+tan^2(x/2))