xsinα-(根号3)y+1=0;
y=sinαx/√3+√3/3=√3sinαx/3+√3/3;
k=√3sinα/3;
-√3/3≤k≤√3/3;
倾斜角范围为[-π/6+kπ,π/6+kπ] (k∈Z)