$g(x)=2x^4+2x^2-24$

$l(x)=3x^8+3x^4-6$

$f(x)=4x^3+2x+1$

$h(x)=4x^8-4x^6+1$

$k(x)=x^4+2x^3-3x^2+x-7$

$f(z)=z^4+z^2-12$

$g(a)=a^{10}-a^5+1$

$k(u)=\frac{1}{4}u^6-\frac{1}{2}u^3+4$

$h(x)=4x^5-2x^3+1$

$l(s)=s^4+3s^3+3$