In 1–2 sentences, explain why the following operation is a closed system under subtraction.

(9x^2+17x+13)−(2x^2+12x+11)

The operation of subtracting (9x^2+17x+13) from (2x^2+12x+11) is a closed system because the resulting expression will still be a polynomial, as all terms have the same degree.

How

Sorry for the confusion. The operation of subtracting (9x^2+17x+13) from (2x^2+12x+11) is a closed system under subtraction because when subtracting polynomials, the result will always be a polynomial.

Explain it

Sure, let me explain it in more detail.

In this case, we are subtracting the polynomial (9x^2+17x+13) from the polynomial (2x^2+12x+11). When we subtract these two polynomials, we combine like terms. Each term is a product of a coefficient and a variable raised to a power.

For example, when subtracting the x^2 terms, we have 2x^2 - 9x^2. This simplifies to -7x^2.

Similarly, when subtracting the x terms, we have 12x - 17x. This simplifies to -5x.

Lastly, when subtracting the constant terms, we have 11 - 13. This simplifies to -2.

So, the result of the subtraction is the polynomial -7x^2 - 5x - 2.

Since the result is still a polynomial with terms of the same degree, it is a closed system under subtraction.

Use the following multiplication problem to show how multiplying polynomials is a closed system. (x^2−1)(−2x+5)

To show that multiplying polynomials is a closed system, we can expand the given expression (x^2−1)(−2x+5) using the distributive property.

(x^2 - 1)(-2x + 5)
= x^2*(-2x) + x^2*5 + (-1)*(-2x) + (-1)*5
= -2x^3 + 5x^2 + 2x - 5

As we can see, the result of multiplying these two polynomials is also a polynomial (-2x^3 + 5x^2 + 2x - 5). Since the result is a polynomial, and thus part of the same system, we can conclude that multiplying polynomials is closed under this operation.