High School

Show that the number is a zero of \( f(x) \) of the given multiplicity, and express \( f(x) \) as a product of linear factors.

\[ f(x) = x^6 − 12x^5 + 45x^4 − 405x^2 + 972x − 729 \]
Zero: 3 (multiplicity 5)

Answer :

Given function, f(x) = x^6 - 12x^5 + 45x^4 - 405x^2 + 972x - 729; 3 (mult. 5).

Zeroes of f(x) are the values of x for which f(x) = 0. So, f(x) is factorable if and only if we can find zeroes of f(x).

Let's solve f(x) = 0 using x = 3 as the initial guess. Then, f(3) = 3^6 - 12(3^5) + 45(3^4) - 405(3^2) + 972(3) - 729 = 0. So, x = 3 is a zero of f(x) of the given multiplicity, which is 5.

Since x = 3 is a zero of f(x) of multiplicity 5, we can represent f(x) as follows:

$$f(x) = (x-3)^5 p(x)$$

where p(x) = EXPRESSF[X] and EXPRESSF[X] is a polynomial expression in x.

Now, we have to find the polynomial expression p(x) so that we can express f(x) as a product of linear factors.

The best way to find p(x) is by polynomial division:

$$\begin{array}{r|rrrrrr} &x^5&-5x^4&30x^3&-90x^2&180x&-243\\hline x-3&x^6&-12x^5&45x^4&-405x^2&972x&-729\\hline &x^6&-3x^5&+18x^4&-45x^3&135x^2&-243x\ & & & &360x^3&-1080x^2&648x\ & & & &360x^3&-1080x^2&648x\ & & & & &1260x^2&-891x\ & & & & &1260x^2&-3780x\ & & & & & &2889x\\end{array}$$

So, p(x) = x^5 - 3x^4 + 18x^3 - 45x^2 + 135x - 243.

Therefore, we can express f(x) as a product of linear factors as follows:

$$\begin{aligned}f(x) &= (x-3)^5 p(x)\ &= (x-3)^5 (x^5 - 3x^4 + 18x^3 - 45x^2 + 135x - 243)\ &= (x-3)^5 (x-3) (x^4 + 2x^3 + 12x^2 + 36x + 81)\ &= (x-3)^6 (x^4 + 2x^3 + 12x^2 + 36x + 81)\ \end{aligned}$$

Therefore, f(x) is a product of linear factors.

For further information on polynomial expressions, refer below:

https://brainly.com/question/29714265

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