Ответ:

[tex]a {}^{2} - b {}^{4} [/tex]

[tex]36a {}^{6} - 81b {}^{8} [/tex]

Объяснение:

[tex]a {}^{2} - b {}^{4} = (a - b {}^{2} )( a {}^{2} + b)[/tex]

[tex]36a {}^{6} - 81b {}^{8} =9\left(4a^{6}-9b^{8}\right) =\left(2a^{3}-3b^{4}\right)\left(2a^{3}+3b^{4}\right) =9\left(2a^{3}-3b^{4}\right)\left(2a^{3}+3b^{4}\right) [/tex]