1) ( 1\5 m - n ) ( 1\25 m² + 1\5mn + n² ) 2) ( 1\2 x - 1\3 y ) ( 1\4 x² + 1\6 xy + 1\9y²)
1) 1/125m^3+1/25m^2n+1/5mn^2-1/25m^2n-1/5mn^2-n^3 1/125m^3-n^3 2) 1/8x^3+1/12x^2y+1/18xy^2-1/12x^2y-1/18xy^2-1/27y^3 1/8x^3-1/27y^3