Find (x^3-x+1) - (3x-1)

X^3 - x + 1 - 3x + 1

= x^3 - 4x + 2

When adding or subtracting polynomials, just combine like terms. If the exponent on the variables are the same, they are like terms.

Before we do that, let's distribute the negative sign to avoid a mistake.

(x^3 - x + 1) + (-3x + 1)

Now add.

x^3 - 4x + 2