[latex]ctg(2pi-frac{x}2) leq 1 \Dziedzina: 2pi-frac{x}2
eq kpi\-frac{x}{2}
eq kpi-2pi\x
eq -2(kpi-2pi)
eq 2kpi\ctg(2pi-frac{x}2) leq 1\ctg(pi+pi-frac{x}2) leq 1\ctg(pi-frac{x}2) leq 1\-ctgfrac{x}x leq 1\ctgfrac{x}2} geq -1\frac{x_0}{2} leq -fracpi4 land frac{x_0}2 geq -pi\frac{x}{2} leq kpi-fracpi4 land frac{x}2 geq kpi-pi[/latex]
[latex]x leq2kpi-fracpi2 land x geq 2kpi-2pi\dla k = 0 x leq -fracpi2 land x geq -2pi
ightarrow x in extless -2pi;-fracpi2 extgreater \dla k = 1 x leq frac32pi land x geq 0
ightarrow x in extless 0; frac32pi extgreater \\Uwzgledniajac dziedzine i zadany przedzial:\x in (-frac32pi,-fracpi2 extgreater cup (0,frac23pi)[/latex]