Explain the steps in multiplying the polynomials. Make sure you include the product in your answer. (x4+7)(5x2+10x−1)

1 answer

To multiply the polynomials \((x^4 + 7)(5x^2 + 10x - 1)\), we will use the distributive property, often called the FOIL method for binomials, but it applies to polynomials of any degree as well. Here are the steps:

Steps to Multiply the Polynomials:

  1. Distribute each term in the first polynomial to each term in the second polynomial. This means you'll take each term in \(x^4 + 7\) and multiply it by each term in \(5x^2 + 10x - 1\).

  2. Multiply \(x^4\) by each term in the second polynomial:

    • Multiply \(x^4 \cdot 5x^2 = 5x^{6}\)
    • Multiply \(x^4 \cdot 10x = 10x^{5}\)
    • Multiply \(x^4 \cdot (-1) = -x^{4}\)
  3. Multiply \(7\) by each term in the second polynomial:

    • Multiply \(7 \cdot 5x^2 = 35x^{2}\)
    • Multiply \(7 \cdot 10x = 70x\)
    • Multiply \(7 \cdot (-1) = -7\)
  4. Combine all the results from the multiplications:

    • From \(x^4\): \(5x^6, 10x^5, -x^4\)
    • From \(7\): \(35x^2, 70x, -7\)
    • So, we combine these: \[ 5x^6 + 10x^5 - x^4 + 35x^2 + 70x - 7 \]
  5. Write the final result in standard form (typically ordered by decreasing degree): \[ 5x^6 + 10x^5 - x^4 + 70x + 35x^2 - 7 \]

Final Answer:

The product of the polynomials \((x^4 + 7)(5x^2 + 10x - 1)\) is: \[ 5x^6 + 10x^5 - x^4 + 35x^2 + 70x - 7 \]