(1)保证tanx及tan(x/2)有意义,有x≠kπ+π/2,x/2≠kπ+π/2,联立解得x≠kπ+π/2且x≠2kπ+π (k∈Z)(2)y=sin2xtanx+sinxtan(x/2)=2sinxcosxsinx/cosx+sinx[(1-cos)/sinx]=2sin²x+1-cos=2(1-cos²x)+1-cosx...