Question

..Пожалуйста, прошу(

Answer 1

$(3x {}^{4} + 9y {}^{3} )(3x {}^{4} - 9y {}^{3} ) = 9x {}^{8} - 81y {}^{6}$

Answer 2

(3х⁴)²-(9у³)²

9х^8-81у^6