To multiply the expression (x^2 - 3x + 1) by (x - a), we need to use the distributive property of multiplication over addition. We start by multiplying each term in the first expression (x^2 - 3x + 1) by (x - a) and then add the resulting terms.
(x^2 - 3x + 1) * (x - a) = x^3 - ax^2 - 3x^2 + 3ax + x - a
= x^3 - (a+3)x^2 + (3a+1)x - a
Therefore, the correct option is:
- x^3 - (a+3)x^2 + (3a+1)x - a