Simplify
-6w^4 + w^2 - (2w^3 + 4w^2 - w)
Simplify brackets
-6w^4 + w^2 - 2w^3 - 4w^2 + w
Collect like terms
-6w^4 + (w^2 - 4w^2) - 2w^3 + w
-6w^4 - 3w^2 - 2w^3 + w
