How to solve (6x^4+30x^3+3x+14) / (x+) in long division. I understand synthetic but not long divison

1 answer

Long division for polynomials involves dividing each term of the polynomial by the divisor, similar to long division with numbers. Here are the steps to solve (6x^4+30x^3+3x+14) / (x+):

1. Write the dividend and divisor in long division format, with the dividend on top and the divisor on the outside to the left.

_______
x+ |6x^4+30x^3+3x+14

2. Divide the first term of the dividend by the first term of the divisor, and write the quotient above the dividend.

6x^3
_______
x+ |6x^4+30x^3+3x+14

3. Multiply the divisor (x+) by the quotient (6x^3) and write the result underneath the first two terms of the dividend.

6x^3
_______
x+ |6x^4+30x^3+3x+14
6x^4+6x^3

4. Subtract the product from step 3 from the first two terms of the dividend, and bring down the next term of the dividend.

6x^3
_______
x+ |6x^4+30x^3+3x+14
6x^4+6x^3
_________
24x^3 + 3x

5. Repeat steps 2-4 with the new dividend (24x^3+3x).

6x^3 + 24x^2
_______
x+ |6x^4+30x^3+3x+14
6x^4+6x^3
_________
24x^3 + 3x
24x^3 + 24x^2
_____________
-21x^2 + 3x

6. Repeat steps 2-4 with the new dividend (-21x^2+3x).

6x^3 + 24x^2 - 21x
_______
x+ |6x^4+30x^3+3x+14
6x^4+6x^3
_________
24x^3 + 3x
24x^3 + 24x^2
_____________
-21x^2 + 3x
-21x^2 - 21x
_____________
24

7. The quotient is 6x^3 + 24x^2 - 21x with a remainder of 24, written as:

6x^3 + 24x^2 - 21x + (24 / (x+))