The division of the polynomial 4x³ + 8x² +x - 3 by x + 1 using the long polynomial division method is 4x² + 4x - 3. See image below for visual explanation.
Division of polynomial using long division.
Long division polynomial is a long process of using a polynomial know as divisor to divide another polynomial called the dividend.
In this question we are to divide:
. To start, we divide the first term of the dividend(4x³) by the first term of the divisor(x) i.e.
.
We write down the calculated result 4x² in the upper part of the table, then multiply it by the divisor 4x² ×(x × 1) = 4x³ + 4x²
Subtract this result from the dividend :
= (4x³ + 8x² + x - 3) - (4x³ + 4x²)
= 4x² + x - 3
Divide the first term of the dividend by the first term of the divisor
, we now write this result to the upper part of the table, Multiply it by the divisor 4x(x + 1) = 4x² + 4x
subtract it from the remainder.
(4x² + x - 3) - (4x² + 4x) = -3x - 3
Divide the first term of the dividend by the first term of the divisor:

Write the result (-3) in the upper part of the table. Multiply the divisor -3(x+1) = -3x - 3
Subtract the result from the remainder.
(-3x - 3) - (-3x - 3) = 0