SOLUTION: Find the quotient of x^5 + 32 divided by x+2

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Question 89662: Find the quotient of x^5 + 32 divided by x+2
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Lets find the quotient using synthetic division

Start with the given polynomial %28x%5E5+%2B+32%29%2F%28x%2B2%29

First lets find our test zero:

x%2B2=0 Set the denominator x%2B2 equal to zero
x=-2 Solve for x.

so our test zero is -2


Now set up the synthetic division table by placing the test zero in the upper left corner and placing the coefficients of the numerator to the right of the test zero.(note: remember if a polynomial goes from 1x%5E5 to 0x%5E3 there is a zero coefficient for x%5E4, x%5E3, x%5E2, and x. This is simply because x%5E5+%2B+32 really looks like 1x%5E5%2B0x%5E4%2B0x%5E3%2B0x%5E2%2B0x%5E1%2B32x%5E0
-2|1000032
|

Start by bringing down the leading coefficient (it is the coefficient with the highest exponent which is 1)
-2|1000032
|
1

Multiply -2 by 1 and place the product (which is -2) right underneath the second coefficient (which is 0)
-2|1000032
|-2
1

Add -2 and 0 to get -2. Place the sum right underneath -2.
-2|1000032
|-2
1-2

Multiply -2 by -2 and place the product (which is 4) right underneath the third coefficient (which is 0)
-2|1000032
|-24
1-2

Add 4 and 0 to get 4. Place the sum right underneath 4.
-2|1000032
|-24
1-24

Multiply -2 by 4 and place the product (which is -8) right underneath the fourth coefficient (which is 0)
-2|1000032
|-24-8
1-24

Add -8 and 0 to get -8. Place the sum right underneath -8.
-2|1000032
|-24-8
1-24-8

Multiply -2 by -8 and place the product (which is 16) right underneath the fifth coefficient (which is 0)
-2|1000032
|-24-816
1-24-8

Add 16 and 0 to get 16. Place the sum right underneath 16.
-2|1000032
|-24-816
1-24-816

Multiply -2 by 16 and place the product (which is -32) right underneath the sixth coefficient (which is 32)
-2|1000032
|-24-816-32
1-24-816

Add -32 and 32 to get 0. Place the sum right underneath -32.
-2|1000032
|-24-816-32
1-24-8160

Since the last column adds to zero, we have a remainder of zero. This means x%2B2 is a factor of x%5E5+%2B+32

Now lets look at the bottom row of coefficients:

The first 5 coefficients (1,-2,4,-8,16) form the quotient

x%5E4+-+2x%5E3+%2B+4x%5E2+-+8x+%2B+16


So %28x%5E5+%2B+32%29%2F%28x%2B2%29=x%5E4+-+2x%5E3+%2B+4x%5E2+-+8x+%2B+16


In other words the quotient is x%5E4+-+2x%5E3+%2B+4x%5E2+-+8x+%2B+16