I don’t understand what these function are like and why they satisfy that f(n) is not O(g(n)) and g(n) is not O(f(n)).

Where is x?

begin{eqnarray}

f(x)=

begin{cases}

k^{2k}, &xin(2π,2π+1)& \

k^{2k+1}, &xin(2π+1,2π+2)&

end{cases}

end{eqnarray}

begin{eqnarray}

g(x)=

begin{cases}

k^{2k-2}, &xin(2π,2π+1)& \

k^{2k+2}, &xin(2π+1,2π+2)&

end{cases}

end{eqnarray}

Also, could you teach me how to write these functions in Grapher on MacOS? Cuz I want to know what they are like.