Master the Mysteries of Polynomial Roots: Unveil the Hidden Power of Multiplicities with f(x) = x(x-1)²

Detailed Analysis of f(x) = x(x-1)² Near x=0

Breaking Down the Factors

The function f(x) = x(x-1)² can be broken down into its individual factors:

  • x: This is a simple linear term with a root at x = 0.
  • (x-1)²: This is a quadratic term with a double root at x = 1.

Behavior of Individual Factors

  • The factor x crosses the x-axis at x = 0 and behaves linearly around this point.
  • The factor (x-1)² has a double root at x = 1 and “bounces” off the x-axis at this point. However, around x = 0, it behaves like a regular quadratic function and takes on positive values.

Overall Behavior Near x=0

When x is close to 0, the term x is close to 0 while (x-1)² is close to 1. Therefore, the overall function f(x) = x(x-1)² will be close to 0.

As x approaches 0 from the left or the right, the function approaches 0 from above, because the term (x-1)² is always positive.

Table of Calculations Close to x=0 for f(x) = x(x-1)²

x Value Near 0 Value of (x-1)² Value of f(x) = x(x-1)²
-0.1 1.21 -0.121
-0.01 1.0001 -0.000010001
-0.001 1.000001 -0.000000001001
0 1 0
0.001 1.000001 0.000000001001
0.01 1.0001 0.000010001
0.1 1.21 0.121



Analysis of f(x) = x(x-1)² Near x=1

Behavior of Individual Factors Near x=1

  • The factor x is a linear term that takes the value 1 when x = 1.
  • The factor (x-1)² is a quadratic term with a double root at x = 1. It “bounces” off the x-axis at this point.

Overall Behavior Near x=1

When x is close to 1, the term x is close to 1, and (x-1)² is close to 0. Therefore, the overall function f(x) = x(x-1)² will be close to 0.

As x approaches 1 from the left or the right, the function approaches 0 from above, because the term (x-1)² is always non-negative.

Table of Calculations Close to x=1 for f(x) = x(x-1)²

x Value Near 1 Value of (x-1)² Value of f(x) = x(x-1)²
0.9 0.01 0.009
0.99 0.0001 0.000099
0.999 0.000001 0.000000999
1 0 0
1.001 0.000001 0.000001001
1.01 0.0001 0.000101
1.1 0.01 0.011


Understanding the Role of Multiplicities in f(x) = x(x-1)²

Exploring Multiplicities

  • The factor x has a single root at x = 0 with a multiplicity of 1. This means the function crosses the x-axis linearly at this point.
  • The factor (x-1)² has a double root at x = 1 with a multiplicity of 2. This means the function “bounces” off the x-axis at this point, rather than crossing it.

Impact on Overall Behavior

When x is close to 1, both x and (x-1)² are close to 1 and 0, respectively. The multiplicity of 2 for the root at x = 1 causes the function to bounce at this point, rather than crossing the x-axis. This bouncing behavior is a direct result of the multiplicity of the root.

Similarly, the function crosses the x-axis at x = 0 because the root at this point has a multiplicity of 1, which is indicative of a simple, linear crossing.

Thus, the multiplicities of the roots have a significant impact on how the function behaves near those roots.