SOLUTION: PlEASE help with polynomial long division.I've tried a million times and just cant get it. :/ (x^3+2x^2+3x-6)/(x-1) and (n^3-27)/(n-3) PlEASE show steps also =) Thanks in advance.

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: PlEASE help with polynomial long division.I've tried a million times and just cant get it. :/ (x^3+2x^2+3x-6)/(x-1) and (n^3-27)/(n-3) PlEASE show steps also =) Thanks in advance.      Log On


   



Question 288025: PlEASE help with polynomial long division.I've tried a million times and just cant get it. :/ (x^3+2x^2+3x-6)/(x-1) and (n^3-27)/(n-3) PlEASE show steps also =) Thanks in advance.
Found 2 solutions by vleith, Theo:
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
Use this URL. It shows all the steps
http://www.calc101.com/webMathematica/long-divide.jsp

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
Polynomial division is not much different than regular long division.
Here's how you do it step by step.

Your dividend is the expression you want to divide into.

It is x%5E3+%2B+2x%5E2+%2B+3x+-+6

Your divisor is the expression you want to divide into the dividend.

It is x-1

You set up your equation as shown in step 1 of the following picture.


***** PICTURE NOT FOUND *****


In step 1 you are dividing x%5E3 by x to get x%5E3+-+x%5E2.

You subtract that from x%5E3+%2B+2x%5E2 to get a remainder of 3x%5E2.

You bring down the 3x from the original dividend as shown in step 1 to make the remainder equal to 3x%5E2+%2B+3x as shown in step 2.

You divide 3x%5E2 of that remainder by x to get 3x which you place above the original dividend as shown in step 1.

You multiply x-1 times 3x to get 3x%5E2+-+3x which you subtract from 3x%5E2+%2B+3x as shown in step 2.

You get a remainder of 6x.

You bring down the -6 from the original dividend as shown in step 1 to get a remainder of 6x-6 as shown in step 3.

You divide x into 6x as shown in step 2 to get 6 which you place above 3x of the original dividend as shown in step 1.

You multiply x-1 times 6 to get 6x-6 which you subtract from 6x-6 to get a remainder of 0 as shown in step 4.

You stop at step 4 because you have nothing left to divide into.

Your answer is x%5E2+%2B+3x+%2B+6 with zero remainder.

To confirm that it's good, you multiply it by x-1 to get the original dividend.

That happens in steps 5 and 6 with the result shown in step 7.

Since you are able to get the same dividend that you started with, your division is good.

The result of your division is x%5E2+%2B+3x+%2B+6 as shown in step 1.

Your original dividend is x%5E3+%2B+2x%5E2+%2B+3x+-+6 as shown in step and confirmed in step 7.

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You are always dividing the highest order of the divider into the highest order of the remainder of the dividend.

You are then always multiplying the whole divisor by the result of that division.

You are then subtracting the result of that multiplication from the remainder.

Once you get your remainder from the division, you are always bringing down the next lower order term from the original dividend.

Follow the steps through and you'll see how it was done.

Now we'll go on to your next problem.

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That problem worked out by hand is shown below:


***** PICTURE NOT FOUND *****


With this problem, you are dividing n%5E3+-+27 by n-1.

Since you are missing lower order exponents in the dividend, you need to fill them in.

That will make further processing easier.

n%5E3+-+27 is equal to n%5E3+%2B+0n%5E2+%2B+0n+-+27 after you fill in the missing lower order exponent terms.

Now you are ready to begin.

You are always dividing the highest order of the divisor into the highest order of the remainder of the dividend.

When you start the division, the remainder of the dividend is the dividend itself.

You Divide n into n%5E3 as shown in step 1.

You get n%5E2 which you place above the n%5E3 as shown in step 1.

You multiply n-3 times n%5E2 to get n%5E3+-+3n%5E2 which you subtract from n%5E3+%2B+0n%5E2 as shown in step 1.

You get a remainder of 3n%5E2 and bring down 0n from the original dividend to get a remainder of 3n%5E2+%2B+0n as shown in step 2.

You divide 3n%5E2 by n to get 3n which you place above 0n%5E2 as shown in step 1.

You multiply n-3 times 3n to get 3n%5E2+-+9n which you subtract from 3n%5E2+%2B+0n as shown in step 2.

You get a remainder of 9n.

You bring down the -27 from the original dividend as shown in step 1.

You get a remainder of 9n-27 as shown in step 3.

You divide 9n by n to get 9.

You place that above the 0n as shown in step 1.

You multiply n-3 by 9 to get 9n+-+27.

You subtract 9n-27 from 9n-27 as shown in step 3 to get a remainder of 0 as shown in step 4.

Since there is nothing left to divide, you are done.

You then confirm the answer is correct by multiplying n%5E2+%2B+3n+%2B+9 as shown in step 1 by n-3 to see if you can get back to the original dividend.

That's done in steps 5 and 6 with the result shown in step 7.

Since you get the original dividend, the division is good.

The result of the division is n%5E2+%2B+3n+%2B+9 as shown in step 1.

The original dividend is n%5E3+-+27 as shown above step 1 and confirmed in step 7.