Question

The final result 4x^4-20x^3+21x^2+20x-25 is also a polynomial. Since we started with polynomials and ended with a polynomial after performing multiplication, this demonstrates that the multiplication of polynomials is a closed system. The result is still within the set of polynomials.

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Answer 1

The final result, \(4x^4 - 20x^3 + 21x^2 + 20x - 25\), is a polynomial. Since we started and ended with polynomials, this shows that multiplying polynomials is closed within the set of polynomials.