Classifying Polynomials

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Name ______________________________________
Advanced Algebra
Date ____________________ Period____
Classifying Polynomials Learning Task
Previously, you have learned about linear functions, which are first degree polynomial functions
that can be written in the form 𝑓(π‘₯) = π‘Ž1 π‘₯1 + π‘Ž0 where π‘Ž1 is the slope of the line and π‘Ž0 is the
y-intercept (Recall:𝑦 = π‘šπ‘₯ + 𝑏, here π‘š is replaced by π‘Ž1 and is𝑏 replaced byπ‘Ž0 .) Also, you
have learned about quadratic functions, which are 2nd degree polynomial functions and can be
expressed as𝑓(π‘₯) = π‘Ž2 π‘₯ 2 + π‘Ž1 π‘₯1 + π‘Ž0 .
These are just two examples of polynomial functions; there are countless others. A polynomial is
a mathematical expression involving a sum of nonnegative integer powers in one or more
variables multiplied by coefficients. A polynomial in one variable with constant coefficients can
be written in the form π‘Žπ‘› π‘₯ 𝑛 + π‘Žπ‘›−1 π‘₯ 𝑛−1 + β‹― + π‘Ž2 π‘₯ 2 + π‘Ž1 π‘₯1 + π‘Ž0 where π‘Žπ‘› ≠ 0the
exponents are all whole numbers, and the coefficients are all real numbers.
1. What are whole numbers?
2. What are real numbers?
3. Decide whether each function below is a polynomial. If it is, write the function in standard
form. If it is not, explain why.
a. 𝑓(π‘₯) = 5π‘₯ 3 + 4π‘₯ 2 + 8π‘₯ + 2
b. 𝑓(π‘₯) = 2π‘₯ 2 + π‘₯ −1
c. 𝑓(π‘₯) = 5 − π‘₯ + 7π‘₯ 3 − π‘₯ 2
d. 𝑓(π‘₯) =
e. 𝑓(π‘₯) =
2π‘₯ 2 −π‘₯ 4 +5+8π‘₯
3
1
3π‘₯ 2
+
f. 𝑓(π‘₯) = 2√π‘₯
6
π‘₯
−2
Name ______________________________________
Advanced Algebra
Date ____________________ Period____
Classifying Polynomials Learning Task
4. Polynomials can be classified by the number terms as well as by the degree of the polynomial.
The degree of the polynomial is the same as the term with the highest degree. Complete the
following chart. Make up your own functions for the last three rows.
Polynomial
Number
of Terms
Classification by
Number of Terms
Degree
Classification by
Degree
𝑓(π‘₯) = 2
monomial
constant
𝑓(π‘₯) = 3π‘₯ − 1
binomial
linear
𝑓(π‘₯) = π‘₯ 2 − 2π‘₯ + 1
trinomial
quadratic
𝑓(π‘₯) = 8π‘₯ 3 + 125
binomial
cubic
𝑓(π‘₯) = π‘₯ 4 − 10π‘₯ + 16
trinomial
quartic
𝑓(π‘₯) = −π‘₯ 5
monomial
quintic
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