(x^3-20x+16) divided by (x-4)

help pls

1 answer

To divide (x^3 - 20x + 16) by (x - 4), you can use polynomial long division or synthetic division.

Here, I will demonstrate synthetic division:

Step 1: Write the coefficients of the dividend and divisor in descending order. For our problem, the coefficients are 1, 0, -20, and 16 for the dividend (x^3 - 20x + 16) and 1 and -4 for the divisor (x - 4).

Step 2: Set up the synthetic division like this:

4 | 1 0 -20 16

Step 3: Bring down the first coefficient (1):

4 | 1 0 -20 16
|-------
1

Step 4: Multiply 4 by 1 and write the result under the second column:

4 | 1 0 -20 16
|-------
1
4

Step 5: Add the numbers in the second column:

4 | 1 0 -20 16
|-------
1
4
------
1

Step 6: Multiply 4 by 1 and write the result under the third column:

4 | 1 0 -20 16
|-------
1
4
------
1
4

Step 7: Add the numbers in the third column:

4 | 1 0 -20 16
|-------
1
4
------
1
4
------
0

The result is 1x^2 + 4x + 0, which simplifies to x^2 + 4x.

Therefore, the division of (x^3 - 20x + 16) by (x - 4) is x^2 + 4x.