− 2 z 2 a 10 − 2 a 10 + 3 z 4 a 8 + 6 z 2 a 8 + 3 a 8 − z 6 a 6 − 2 z 4 a 6 − 2 z 2 a 6 − 2 a 6 + 2 z 4 a 4 + 4 z 2 a 4 + 2 a 4 {\displaystyle -2z^{2}a^{10}-2a^{10}+3z^{4}a^{8}+6z^{2}a^{8}+3a^{8}-z^{6}a^{6}-2z^{4}a^{6}-2z^{2}a^{6}-2a^{6}+2z^{4}a^{4}+4z^{2}a^{4}+2a^{4}}
