valenivan

Verified answer

=∛(12mn²-6m²n)-(8n³-m³) / 2n-m = ∛(2n-m)6mn-(2n-m)(4n²+2mn+m²) /2n-m =
∛(2n-m )(6mn-4n²-2mn-m²) /2n-m = ∛ - (2n-m)(4n²-4mn+m²) /2n-m =∛-(2n-m)(2n-m)² /2n-m = - ∛(2n-m)³ / 2n-m =-1