Chapter 4 - Section 4.2 - Adding and Subtracting Polynomials - 4.2 Exercises - Page 285: 58

$2x^5-x^4-2x^3+1$

Removing the grouping symbols and then combining like terms, the given expression, $ (2x^5-2x^4+x^3-1)+(x^4-3x^3+2) ,$ simplifies to \begin{array}{l}\require{cancel} 2x^5-2x^4+x^3-1+x^4-3x^3+2 \\\\= 2x^5+(-2x^4+x^4)+(x^3-3x^3)+(-1+2) \\\\= 2x^5-x^4-2x^3+1 .\end{array}