1. **State the problem:** Multiply the two polynomials $$(x^2 + 2x - 1)(x^2 - x - 4)$$.
2. **Recall the distributive property:** To multiply two polynomials, multiply each term in the first polynomial by each term in the second polynomial.
3. **Multiply each term:**
- $x^2 \cdot x^2 = x^4$
- $x^2 \cdot (-x) = -x^3$
- $x^2 \cdot (-4) = -4x^2$
- $2x \cdot x^2 = 2x^3$
- $2x \cdot (-x) = -2x^2$
- $2x \cdot (-4) = -8x$
- $-1 \cdot x^2 = -x^2$
- $-1 \cdot (-x) = +x$
- $-1 \cdot (-4) = +4$
4. **Combine all terms:**
$$x^4 - x^3 - 4x^2 + 2x^3 - 2x^2 - 8x - x^2 + x + 4$$
5. **Group like terms:**
- $x^4$
- $(-x^3 + 2x^3) = x^3$
- $(-4x^2 - 2x^2 - x^2) = -7x^2$
- $(-8x + x) = -7x$
- $4$
6. **Write the simplified polynomial:**
$$x^4 + x^3 - 7x^2 - 7x + 4$$
**Final answer:** $$x^4 + x^3 - 7x^2 - 7x + 4$$
Polynomial Multiplication 6248F6
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