Cogito
Integrated Math 3 · Chapter 1 · Lesson 1
Polynomial Behaviour
Degree and leading coefficient decide the ends.
12 problems · about 21 minutes · F-IF.C.7, A-APR.B.3
Figure — use these to answer the problems
Warm Up
Straightforward practice. Get the method working first.
5 problemsA degree-4 polynomial. At most how many turning points?
AnswerWhat decides end behaviour?
- The degree and the sign of the leading coefficient.
- The constant term.
f(x) = 3x⁴. How many ends go up?
Answerf(x) = −3x⁴. How many ends go up?
Answerf(x) = 2x⁵. How many ends go up?
Answer
Build It Up
The same ideas with more to keep track of.
3 problemsA degree-6 polynomial. At most how many turning points?
Answer(x − 3)²(x + 1) = 0. Multiplicity of the root 3?
AnswerAt an even multiplicity, does the graph cross the axis? 1 yes, 0 no.
Answer
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
4 problemsSort each polynomial by its end behaviour.
Write each item under the heading it belongs to: Degree 2 · Degree 4 · Degree 3 · Degree 5
Both ends the same way
Ends go opposite ways
A degree-3 polynomial. How many roots in total?
AnswerThe Turns
A degree-5 polynomial. At most how many turning points?
AnswerThe Roots
A degree-5 polynomial. How many roots, counting repeats and complex ones?
Answer