To factor the expression ³ + 125 completely, we can use the formula for the sum of cubes, which is ³ + ³ = ( + )(² − + ²). In this case, ³ + 125 can be written as ( + 5)(² − 5 + 25). So, the expression is completely factored as ( + 5)(² − 5 + 25). Hope this helps!