question form

#$&*

MTH 158

Your 'question form' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

** Question Form_labelMessages **

Multiplying Polynomials

** **

Chapter R.4; Question 87.

** **

I know how to multiply two polynomials together but when we add the third one, I get lost. I've tried doing this problem several different ways and always come close to the answer but never exact. I can't figure out what I'm doing wrong for:

(2x + 1)^3

@& We can start by saying that

(2x + 1)^ 3 = (2x + 1) * (2x + 1)^2

Now let's find (2x + 1)^2:

(2x+1)^2 = (2x + 1) * (2x + 1) = 2x * ( 2x + 1) + 1 * (2x + 1) = 4 x^2 + 2x + 2x + 1 = 4 x^2 + 4 x + 1.

So

(2x + 1)^ 3 = (2x + 1) * (2x + 1)^2 = (2x + 1) * ( 4 x^2 + 4 x + 1) = 2x * ( 4 x^2 + 4 x + 1) + 1 * ( 4 x^2 + 4 x + 1) = 8 x^3 + 8 x^2 + 2 x + 4 x^2 + 4 x + 1 = 8 x^3 + 8 x^2 + 4 x^2 + 2 x + 4 x + 1 = 8 x^3 + 12 x^2 + 6 x + 1. *@

question form

#$&*

MTH 158

Your 'question form' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

** Question Form_labelMessages **

Multiplying Polynomials

** **

Chapter R.4; Question 87.

** **

I know how to multiply two polynomials together but when we add the third one, I get lost. I've tried doing this problem several different ways and always come close to the answer but never exact. I can't figure out what I'm doing wrong for:

(2x + 1)^3

@& We can start by saying that

(2x + 1)^ 3 = (2x + 1) * (2x + 1)^2

Now let's find (2x + 1)^2:

(2x+1)^2 = (2x + 1) * (2x + 1) = 2x * ( 2x + 1) + 1 * (2x + 1) = 4 x^2 + 2x + 2x + 1 = 4 x^2 + 4 x + 1.

So

(2x + 1)^ 3 = (2x + 1) * (2x + 1)^2 = (2x + 1) * ( 4 x^2 + 4 x + 1) = 2x * ( 4 x^2 + 4 x + 1) + 1 * ( 4 x^2 + 4 x + 1) = 8 x^3 + 8 x^2 + 2 x + 4 x^2 + 4 x + 1 = 8 x^3 + 8 x^2 + 4 x^2 + 2 x + 4 x + 1 = 8 x^3 + 12 x^2 + 6 x + 1. *@

question form

#$&*

MTH 158

Your 'question form' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

** Question Form_labelMessages **

Multiplying Polynomials

** **

Chapter R.4; Question 87.

** **

I know how to multiply two polynomials together but when we add the third one, I get lost. I've tried doing this problem several different ways and always come close to the answer but never exact. I can't figure out what I'm doing wrong for:

(2x + 1)^3

@&

We can start by saying that

(2x + 1)^ 3 = (2x + 1) * (2x + 1)^2

Now let's find (2x + 1)^2:

(2x+1)^2 = (2x + 1) * (2x + 1)

= 2x * ( 2x + 1) + 1 * (2x + 1)

= 4 x^2 + 2x + 2x + 1

= 4 x^2 + 4 x + 1.

So

(2x + 1)^ 3 = (2x + 1) * (2x + 1)^2

= (2x + 1) * ( 4 x^2 + 4 x + 1)

= 2x * ( 4 x^2 + 4 x + 1) + 1 * ( 4 x^2 + 4 x + 1)

= 8 x^3 + 8 x^2 + 2 x + 4 x^2 + 4 x + 1

= 8 x^3 + 8 x^2 + 4 x^2 + 2 x + 4 x + 1

= 8 x^3 + 12 x^2 + 6 x + 1.

*@

question form

#$&*

MTH 158

Your 'question form' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

** Question Form_labelMessages **

Multiplying Polynomials

** **

Chapter R.4; Question 87.

** **

I know how to multiply two polynomials together but when we add the third one, I get lost. I've tried doing this problem several different ways and always come close to the answer but never exact. I can't figure out what I'm doing wrong for:

(2x + 1)^3

@&

We can start by saying that

(2x + 1)^ 3 = (2x + 1) * (2x + 1)^2

Now let's find (2x + 1)^2:

(2x+1)^2 = (2x + 1) * (2x + 1)

= 2x * ( 2x + 1) + 1 * (2x + 1)

= 4 x^2 + 2x + 2x + 1

= 4 x^2 + 4 x + 1.

So

(2x + 1)^ 3 = (2x + 1) * (2x + 1)^2

= (2x + 1) * ( 4 x^2 + 4 x + 1)

= 2x * ( 4 x^2 + 4 x + 1) + 1 * ( 4 x^2 + 4 x + 1)

= 8 x^3 + 8 x^2 + 2 x + 4 x^2 + 4 x + 1

= 8 x^3 + 8 x^2 + 4 x^2 + 2 x + 4 x + 1

= 8 x^3 + 12 x^2 + 6 x + 1.

*@