z 3 a 7 + 3 z 4 a 6 − z 2 a 6 + 5 z 5 a 5 − 5 z 3 a 5 + 2 z a 5 + 5 z 6 a 4 − 7 z 4 a 4 + 4 z 2 a 4 − a 4 + 2 z 7 a 3 + 3 z 5 a 3 − 10 z 3 a 3 + 4 z a 3 + 8 z 6 a 2 − 18 z 4 a 2 + 10 z 2 a 2 − 2 a 2 + 2 z 7 a − z 5 a − 6 z 3 a + 3 z a + 3 z 6 − 8 z 4 + 5 z 2 + z 5 a − 2 z 3 a + z a {\displaystyle z^{3}a^{7}+3z^{4}a^{6}-z^{2}a^{6}+5z^{5}a^{5}-5z^{3}a^{5}+2za^{5}+5z^{6}a^{4}-7z^{4}a^{4}+4z^{2}a^{4}-a^{4}+2z^{7}a^{3}+3z^{5}a^{3}-10z^{3}a^{3}+4za^{3}+8z^{6}a^{2}-18z^{4}a^{2}+10z^{2}a^{2}-2a^{2}+2z^{7}a-z^{5}a-6z^{3}a+3za+3z^{6}-8z^{4}+5z^{2}+{\frac {z^{5}}{a}}-{\frac {2z^{3}}{a}}+{\frac {z}{a}}}
