SOLUTION: Simplify {{{ (3x^3-19x^2+27x+4) / (x-4)}}}

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Question 143675: Simplify +%283x%5E3-19x%5E2%2B27x%2B4%29++%2F+%28x-4%29
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Let's simplify this expression using synthetic division


Start with the given expression %283x%5E3+-+19x%5E2+%2B+27x+%2B+4%29%2F%28x-4%29

First lets find our test zero:

x-4=0 Set the denominator x-4 equal to zero

x=4 Solve for x.

so our test zero is 4


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.
4|3-19274
|

Start by bringing down the leading coefficient (it is the coefficient with the highest exponent which is 3)
4|3-19274
|
3

Multiply 4 by 3 and place the product (which is 12) right underneath the second coefficient (which is -19)
4|3-19274
|12
3

Add 12 and -19 to get -7. Place the sum right underneath 12.
4|3-19274
|12
3-7

Multiply 4 by -7 and place the product (which is -28) right underneath the third coefficient (which is 27)
4|3-19274
|12-28
3-7

Add -28 and 27 to get -1. Place the sum right underneath -28.
4|3-19274
|12-28
3-7-1

Multiply 4 by -1 and place the product (which is -4) right underneath the fourth coefficient (which is 4)
4|3-19274
|12-28-4
3-7-1

Add -4 and 4 to get 0. Place the sum right underneath -4.
4|3-19274
|12-28-4
3-7-10

Since the last column adds to zero, we have a remainder of zero. This means x-4 is a factor of 3x%5E3+-+19x%5E2+%2B+27x+%2B+4

Now lets look at the bottom row of coefficients:

The first 3 coefficients (3,-7,-1) form the quotient

3x%5E2+-+7x+-+1


So %283x%5E3+-+19x%5E2+%2B+27x+%2B+4%29%2F%28x-4%29 simplifies to 3x%5E2+-+7x+-+1


In other words, %283x%5E3+-+19x%5E2+%2B+27x+%2B+4%29%2F%28x-4%29=3x%5E2+-+7x+-+1 where x%3C%3E4.