Expand and simplify the expression \((3x^2 - 2x + 1)(2x^2 + x - 3)\)

Step 1 ：Firstly, we must distribute each term in the first polynomial to every term in the second polynomial. This gives us: \(3x^2 * 2x^2 + 3x^2 * x + 3x^2 * -3 - 2x * 2x^2 - 2x * x - 2x * -3 + 1 * 2x^2 + 1 * x - 1 * 3\)

Step 2 ：This simplifies to: \(6x^4 + 3x^3 - 9x^2 - 4x^3 - 2x^2 + 6x + 2x^2 + x - 3\)

Step 3 ：Combine like terms: \(6x^4 - x^3 - 9x^2 + 7x - 3\)