Chapter 4 - Section 4.2 - Adding and Subtracting Polynomials - 4.2 Exercises - Page 285: 57

$5y^3-3y^2+5y+1$

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