Which of the following responses demonstrates that polynomials form a closed system under multiplication?(1 point)

Responses

(√x)(x+1)

(x^2/2)(1x)

(x^2+1)(x−1/2)

x^2+2x+1

1 answer

To determine which of the given responses demonstrates that polynomials form a closed system under multiplication, we need to ensure that the product of two polynomial expressions results in another polynomial.

Let's analyze each of the responses:

  1. (√x)(x+1):

    • Here, √x is not a polynomial, as it contains a fractional exponent (1/2). Therefore, their product is not guaranteed to be a polynomial.
  2. (x^2/2)(1x):

    • This simplifies to (1/2)x^3, which is a polynomial.
  3. (x^2+1)(x−1/2):

    • The first expression, x^2 + 1, is a polynomial, and x - 1/2 is also a polynomial. The product of two polynomials is also a polynomial.
  4. x^2 + 2x + 1:

    • This is already a polynomial, but it is not a product of polynomials, so it doesn't demonstrate the closure property under multiplication.

Based on this reasoning, the responses that demonstrate that polynomials form a closed system under multiplication are:

  • (x^2/2)(1x)
  • (x^2+1)(x−1/2)

If you need a single option that best demonstrates the closure property, it would be (x^2+1)(x−1/2), as it explicitly shows the multiplication of two polynomials resulting in another polynomial.