Core Connections Integrated III, 2015
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Core Connections Integrated III, 2015 View details
1. Section 8.1
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Exercise 8 Page 376

Practice makes perfect
a

Let's calculate the corresponding y-values for the given x-values. We will only be substituting integers for x.

x (x-1)^2(x+1) y
-2 ( -2-1)^2( -2+1) -9
-1 ( -1-1)^2( -1+1) 0
0 ( 0-1)^2( 0+1) 1
1 ( 1-1)^2( 1+1) 0
2 ( 2-1)^2( 2+1) 3
Let's simplify our table.

x y
- 2 - 9
- 1 0
0 1
1 0
2 3

Finally, we will plot the points in a coordinate plane and draw the graph.

b

Let's calculate the corresponding y-values for the given x-values.

x (x-1)^2(x+1)^2 y
-2 ( -2-1)^2( -2+1)^2 9
-1 ( -1-1)^2( -1+1)^2 0
0 ( 0-1)^2( 0+1)^2 1
1 ( 1-1)^2( 1+1)^2 0
2 ( 2-1)^2( 2+1)^2 9
Let's simplify our table.

x y
- 2 9
- 1 0
0 1
1 0
2 9

Finally, we will plot the points in a coordinate plane and draw the graph.

c

Let's calculate the corresponding y-values for the given x-values.

x x^3-4x y
-2 ( -2)^3-4( -2) 0
-1 ( -1)^3-4( -1) 3
0 ( 0)^3-4( 0) 0
1 ( 1)^3-4( 1) -3
2 ( 2)^3-4( 2) 0
Let's simplify our table.

x y
- 2 0
- 1 3
0 0
1 - 3
2 0

Finally, we will plot the points in a coordinate plane and draw the graph.

d

In order to tell the degree of each of the polynomials from Parts A to C, we should first write them in standard form.

y=a_n x^n + a_(n-1)x^(n-1) + ⋯ + a_1 x^1 + a_0x^0 Notice that the function from Part C is already written in standard form. This means that we can identify the degree by finding the highest power to which x is raised. c. y=x^3-4x The polynomial from Part C has a degree of 3. Let's move on to the polynomials from Parts A and B, which require us to rewrite them in standard form. We will start with Part A.

y=(x-1)^2(x+1)
y=(x-1)(x-1)(x+1)
â–¼
Simplify right-hand side

(a-b)(a+b)=a^2-b^2

y=(x-1)(x^2-1^2)
y=(x-1)(x^2-1)
y=x^3-x-x^2+1
y=x^3-x^2-x+1
Looking at the rewritten polynomial, we can see that the largest power that x is raised to is 3. This means that it is also a {\color{#FF0000}{3}}^\text{rd} degree polynomial. a. y=x^3-x^2-x+1 Finally, let's rewrite the polynomial from Part B in standard form.

y=(x-1)^2(x+1)^2
y=(x-1)(x-1)(x+1)(x+1)
â–¼
Simplify right-hand side
y=(x-1)(x+1)(x-1)(x+1)

(a-b)(a+b)=a^2-b^2

y=(x^2-1^2)(x^2-1^2)
y=(x^2-1)(x^2-1)
y=x^4-x^2-x^2+1
y=x^4-2x^2+1

The largest power that x is raised to is 4, meaning that this is a {\color{#FF0000}{4}}^\text{th} degree polynomial. b. y=x^4-2x^2+1