QuestionNAME
DATE
PERIOD
7. For each polynomial (a) write the degree (b) leading coefficient (c) zeros (d) describe the end behavior and (e) sketch a possible graph. You can then check your sketch using graphing technology.
\begin{tabular}{|l|c|c|}
\hline \multicolumn{3}{|c|}{} \\
\hline Degree & Leading Coefficient & Zeros \\
\hline
\end{tabular}
End Behavior
As x gets larger and larger negative, gets larger and larger .
As gets larger and larger positive, gets larger and larger
Studdy Solution
STEP 1
What is this asking?
We need to find some key features of a polynomial like its degree, leading coefficient, zeros, and end behavior, and then sketch its graph!
Watch out!
Don't mix up the leading coefficient and the constant term.
Also, remember the connection between the zeros and the factors of the polynomial.
STEP 2
1. Find the Degree
2. Find the Leading Coefficient
3. Find the Zeros
4. Describe the End Behavior
5. Sketch the Graph
STEP 3
The **degree** of a polynomial is the highest power of when it's fully expanded.
Our polynomial is in factored form.
STEP 4
Imagine multiplying it all out.
We'd have multiplied by itself four times, which would give us as the highest power term.
So, the **degree** is **4**!
STEP 5
The **leading coefficient** is the number multiplying the highest power of .
STEP 6
When we multiply out , the term with the highest power of comes from multiplying the from each factor: .
So, the **leading coefficient** is **-1**.
STEP 7
The **zeros** of a polynomial are the values of that make the polynomial equal to zero.
STEP 8
Since is factored, we can see that the zeros are the values that make each factor equal to zero.
So, the **zeros** are , , , and .
STEP 9
The **end behavior** describes what happens to the polynomial as gets very large (positive or negative).
STEP 10
Since our **leading coefficient** is **negative** and the **degree** is **even**, both ends of the graph will point downwards.
As gets very large and negative, gets very large and negative.
As gets very large and positive, also gets very large and negative.
STEP 11
We know the **zeros** are at , , , and , so the graph crosses the x-axis at these points.
STEP 12
Since the **degree** is **4**, the graph can have up to three turning points.
STEP 13
We also know the **end behavior**: both ends point down.
STEP 14
With this information, we can sketch a graph that passes through the zeros and has the correct end behavior.
It'll look something like a "W" flipped upside down!
STEP 15
\begin{array}{lcc}
\multicolumn{3}{c}{A(x)=-(x+4)(x+1)(x-3)(x-8)} \\
\text{Degree} & 4 & \text{Zeros} \\
\text{Leading Coefficient} & -1 & -4, -1, 3, 8 \\
\end{array}
End Behavior:
As gets larger and larger negative, gets larger and larger **negative**.
As gets larger and larger positive, gets larger and larger **negative**.
(See the sketch described in step 2.5, which should resemble an upside-down "W" passing through the zeros.)
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