Core Connections Algebra 2, 2013
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Core Connections Algebra 2, 2013 View details
1. Section 8.1
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Exercise 17 Page 377

Practice makes perfect
a Polynomials are expressions that can be written as a sum of terms of the form.

(any number)* x^((whole number)) Let's check if the terms follow the description of a polynomial. ( any number)* x^(( whole number)) ↓ y= 3x^2+ 2x^2+ 1x^1 As we can see, the equation is a polynomial.

b Let's start by simplifying the equation.
y=(x-1)^2(x-2)^2
â–Ľ
Simplify right-hand side
y=(x^2-2x+1)(x^2-4x+4)
y=x^4-4x^3+4x^2-2x^3+8x^2-8x+x^2-4x+4
y=x^4-6x^3+13x^2-12x+4
Now we can rewrite the terms and analyze the expression. ( any number)* x^(whole number) ↓ y= 1x^4- 6x^3+ 13x^2- 12x^1+ 4x^0 The equation is a polynomial.
c Examining the function, we notice that it contains a term that does not follow the description of a polynomial.

( any number)* x^(whole number) ↓ y= 1x^2+ 2^x Therefore, this function is not a polynomial.

d Let's attempt to rewrite the terms so that they match the look of a polynomial.

( any number)* x^(whole number) ↓ y= 3x^1- 1x^0 This function is a polynomial.

e Before we can determine if this is a polynomial, we have to simplify it.
y=(x-2)^2-1
y=x^2-4x+4-1
y=x^2-4x+3
Now we can rewrite the terms and analyze the expression. ( any number)* x^(whole number) ↓ y= 1x^2- 4x^1+ 3x^0 The function is a polynomial.
f Notice that y is squared. A polynomial function is one where y is isolated. Therefore, we should begin by isolating y.
y^2=(x-2)^2-1
y=± sqrt((x-2)^2-1)
Having solved for y, we see immediately that the function does not match the look of a polynomial.
g Notice that an expression in the form 1a^b can be rewritten as a^(-b). With this information, we can rewrite the equation and determine if it is a polynomial.

( any number)* x^(whole number) ↓ y= 1x^(-2)+ 1x^(-1)+ 1/2x^0 As we can see, the function is not a polynomial.

h Again, let's rewrite the expression and try to match the terms with the look of a polynomial.

( any number)* x^(whole number) ↓ y= 1/2x^1+ 1/3x^0 The function is a polynomial.

i Again, let's rewrite the expression and try to match the terms with the look of a polynomial.

( any number)* x^(whole number) ↓ y= 1x^1 The function is a polynomial.

j Let's rewrite the expression and try to match the terms with the look of a polynomial.

( any number)* x^(whole number) ↓ y= - 7x^0 The function is a polynomial.