Answer :

Alright, let's analyze and understand the given polynomial step by step. The polynomial in question is:

[tex]\[ x^4 - 5x^3 + 8x^2 - 5x - 1. \][/tex]

This is a fourth-degree polynomial. Here are the detailed aspects and steps one might follow to handle such a polynomial:

1. Understand the Polynomial: This polynomial is a quartic polynomial which means it has a degree of 4.

2. Identify the Coefficients: The general form of the polynomial is:
[tex]\[ ax^4 + bx^3 + cx^2 + dx + e \][/tex]
For the given polynomial, the coefficients are:
[tex]\[ \begin{align*} a &= 1 \quad (\text{for } x^4), \\ b &= -5 \quad (\text{for } x^3), \\ c &= 8 \quad (\text{for } x^2), \\ d &= -5 \quad (\text{for } x), \\ e &= -1 \quad (\text{constant term}). \end{align*} \][/tex]

3. Roots of the Polynomial: Finding the roots of a quartic polynomial (determining the values of [tex]\(x\)[/tex] that satisfy the polynomial equation [tex]\( x^4 - 5x^3 + 8x^2 - 5x - 1 = 0 \)[/tex]) can be complex. Analytical methods for finding roots of such polynomials include:
- Factoring, if possible.
- Using numerical methods or computer algebra systems for exact results.
- Applying the Rational Root Theorem to test possible rational roots.
- Using formulas for roots of quartic equations (though these are quite complex).

4. Factorization: Factoring such polynomials manually can be difficult. Often, determining factors would require checking various combinations.

5. Graphical Representation: By plotting this polynomial function [tex]\( f(x) = x^4 - 5x^3 + 8x^2 - 5x - 1 \)[/tex], one can visually assess the behavior of the polynomial:
- Determine where the curve intersects the x-axis, which indicates real roots.
- Observe the direction of the end behavior (for very large positive or negative x, the polynomial will tend to positive because the leading coefficient [tex]\(a = 1\)[/tex] is positive).

6. Derivative Analysis for Critical Points: To find critical points or where the function changes direction, we take the first derivative:
[tex]\[ f'(x) = 4x^3 - 15x^2 + 16x - 5. \][/tex]
Setting [tex]\( f'(x) = 0 \)[/tex] will help identify where the slope of the polynomial is zero, indicating potential local maxima, minima, or inflection points.

7. Second Derivative for Concavity: Examining the second derivative gives information about concavity and inflection points:
[tex]\[ f''(x) = 12x^2 - 30x + 16. \][/tex]
By solving [tex]\( f''(x) = 0 \)[/tex], we can find inflection points where the concavity changes.

8. Analyzing Behavior at Infinity: As [tex]\( x \to \infty \)[/tex] or [tex]\( x \to -\infty \)[/tex], the polynomial [tex]\( x^4 - 5x^3 + 8x^2 - 5x - 1 \)[/tex] is dominated by the term [tex]\( x^4 \)[/tex]. Since the coefficient of [tex]\( x^4 \)[/tex] is positive (1), the polynomial will go to positive infinity as [tex]\( x \)[/tex] moves to positive or negative infinity.

In summary, the polynomial [tex]\( x^4 - 5x^3 + 8x^2 - 5x - 1 \)[/tex] is a standard quartic polynomial with specific coefficients that determine its shape and roots. The key aspects include its degree (4), coefficients of each term, possible roots, critical points determined by the first derivative, and concavity shown by the second derivative. These points form the foundation for analyzing and understanding the behavior and properties of the given polynomial.