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You have learned how to divide polynomials in three different ways: by factoring, by long division, and by synthetic division. Explain in words and with mathematical representations how you would divide this polynomial in each of the three ways.

You have learned how to divide polynomials in three different ways: by factoring, by-example-1

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Answer:

Step-by-step explanation:

Given:


\frac{6x^3+24x^2-2x-8}{x\text{ + 4}}

To find:

To divide polynomials using factoring, long division, and synthetic division

NB: In the absence of example on factoring method, we will only be considering long division and synthetic division

Using long division:

For long division, the divisor will be outside(x + 4) while the expression to be divided (6x³ + 24x² - 2x - 8) will be inside the dividing section.

Divide 6x³ by x. The result is 6x². Write the result at the quotient. Then multiply 6x² by (x + 4). This gives 6x³ + 24x². Subtract 6x³ + 24x² from the original expression. 6x³ + 24x² cancels out. We will be left with -2x - 8.

Divided -2x by x. This gives -2. Write this at the quotient. Multiply -2 by (x + 4). The result is -2x - 8. Subtract -2x -8 from (-2x - 8). The result is zero. This means there is no remainder.

The result of the division is 6x²- 2

Using synthetic division:

For this division, the coefficients are used. The coefficients of the polynomial 6x³ + 24x² - 2x - 8 are 6, 24, -2, -8

The divisor used in the division is the value of x when x + 4 is equated to zero

x + 4 = 0

x = -4

We bring down the first coefficient beneath the line.

1) Multiply that coefficient by the divisor (-4). This gives -24. Write -24 in the 2nd row. Add this result to the coefficient at the top (24). The result is 0

2) Multiply -4 by 0. The result will be written in the 2nd row under the next coefficient (-2). Add 0 to -2. 3) The result -2 is multiplied by -4. We get 8. This is added to the next coefficient (8). The sum gives 0

When the last number of a synthetic division is zero, it means there is no remainder. It was factorized completely.

The final result of the division from the synthetic division:


\begin{gathered} \frac{6x³+24x²-2x-8}{x\text{ + 4}}\text{ = Quotient + }(remainder)/(divisor) \\ \\ The\text{ coeffciient remaining = 6, 0 , 2} \\ To\text{ write back in the form of expression, the first coefficient will have x}^2,\text{ next x, the last will be 0} \\ The\text{ term \lparen exponent\rparen decreases after the division. The highest exponent was 3. } \\ =\text{ 6x}^2\text{ + 0x + 2 + }\frac{0}{x\text{ + 4}} \\ \\ =\text{ 6x}^2\text{ + 0 + 2 + 0} \\ \\ =\text{ 6x}^2\text{ + 2} \end{gathered}

You have learned how to divide polynomials in three different ways: by factoring, by-example-1
You have learned how to divide polynomials in three different ways: by factoring, by-example-2
User Avinash Reddy
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