This lesson will show how to find the multiplicity of a zero with a few good examples.
The zero of a polynomial function is the value or number that will make the polynomial function equal to 0. When the zero of a polynomial function is repeated, it is called a multiple zero. The multiplicity of a zero is equal to the number of times the zero is repeated.
Example #1
Find any multiple zeros of f(x) = x2(x + 10)(x - 5)3 and state the multiplicity of all zeros.
The zeros of the function are 0, -10, and 5 since these values will make the function equal to 0. The numbers 0 and 5 are multiple zeros of the polynomial function.
The multiplicity of 0 is 2 and the multiplicity of 5 is 3
Example #2
Find any multiple zeros of f(x) = x(x + 1)5(x - 3)4(2x + 4)6 and state the multiplicity of all zeros.
The zeros of the function are 0, -1, 3 and -2 since these values will make the function equal to 0. The numbers -1, 3, and -2 are multiple zeros of the polynomial function.
The multiplicity of -1 is 5, the multiplicity of 3 is 4, and the multiplicity of -2 is 6
Example #3
Find any multiple zeros of f(x) = x4 - 4x3 + 4x2 and state the multiplicity of all zeros.
First, factor the function so you can clearly identify the zeros.
f(x) = x4 - 4x3 + 4x2
f(x) = x2(x2 - 4x + 4)
f(x) = x2(x - 2)(x - 2)
f(x) = x2(x - 2)2
The zeros of the function are 0 and 2 since these values will make the function equal to 0. The numbers 0 and 2 are multiple zeros of the polynomial function.
The multiplicity of 0 is 2 and the multiplicity of 2 is 2.