`(x^(3)-2x^(2)-3)xx(-x)`

Answer

To solve the expression \((x^3 - 2x^2 - 3)(-x)\), we will follow these steps:

### Step 1: Distribute \(-x\) to each term in the polynomial
We will multiply \(-x\) by each term in the polynomial \(x^3 - 2x^2 - 3\).

\[ -x \cdot x^3, \quad -x \cdot (-2x^2), \quad -x \cdot (-3) \]

### Step 2: Perform the multiplication
Now we will calculate each multiplication:

1. \(-x \cdot x^3 = -x^{3+1} = -x^4\)
2. \(-x \cdot (-2x^2) = 2x^{2+1} = 2x^3\) (Note: Negative times negative gives a positive)
3. \(-x \cdot (-3) = 3x\) (Again, negative times negative gives a positive)

### Step 3: Combine the results
Now we combine all the terms we calculated:

\[ -x^4 + 2x^3 + 3x \]

### Final Result
Thus, the final expression after multiplying \((x^3 - 2x^2 - 3)\) by \(-x\) is:

\[ -x^4 + 2x^3 + 3x \]

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