Answer
$$13x^3 + x^2 - x - 24$$
Work Step by Step
To simplify this expression we need to get rid of the parentheses and perform the addition or subtraction as specified. To get rid of the parentheses, we combine the operation in front of the parentheses with the sign in front of each of the terms inside the parentheses:
$$7x^3 + 3x^2 - 5x - 11 + 6x^3 - 2x^2 + 4x - 13$$
Now we combine like terms:
$$13x^3 + x^2 - x - 24$$
