Question

How do you combine like terms in `(- x ^ { 3} + 8x ^ { 2} + 8x - 11) - ( 10x ^ { 3} - x ^ { 2} - 2x + 10)`?

Answer 1

`-11x^3+9x^2+10x-21`

Explanation:

`(- x ^ { 3} + 8x ^ { 2} + 8x - 11) - ( 10x ^ { 3} - x ^ { 2} - 2x + 10)`

Remove parentheses and change signs as needed
`-x^3+8x^2+8x-11-10x^3+x^2+3x-10`

Group like terms together
`(-x^3-10x^3)+(8x^2+x^2)+(8x+2x)+(-11-10)`

Combine the like terms
`(-11x^3)+(9x^2)+(10x)+(-21)`

Remove parentheses, change signs where necessary
`-11x^3+9x^2+10x-21`

Done! :D