Examples
f(x)=x2-5x+4f(x)=x2−5x+4 , x=-4
Step 1
Set up the long division problem to evaluate the function at -4.
x2-5x+4x-(-4)
Step 2
Step 2.1
Place the numbers representing the divisor and the dividend into a division-like configuration.
-4 | 1 | -5 | 4 |
Step 2.2
The first number in the dividend (1) is put into the first position of the result area (below the horizontal line).
-4 | 1 | -5 | 4 |
1 |
Step 2.3
Multiply the newest entry in the result (1) by the divisor (-4) and place the result of (-4) under the next term in the dividend (-5).
-4 | 1 | -5 | 4 |
-4 | |||
1 |
Step 2.4
Add the product of the multiplication and the number from the dividend and put the result in the next position on the result line.
-4 | 1 | -5 | 4 |
-4 | |||
1 | -9 |
Step 2.5
Multiply the newest entry in the result (-9) by the divisor (-4) and place the result of (36) under the next term in the dividend (4).
-4 | 1 | -5 | 4 |
-4 | 36 | ||
1 | -9 |
Step 2.6
Add the product of the multiplication and the number from the dividend and put the result in the next position on the result line.
-4 | 1 | -5 | 4 |
-4 | 36 | ||
1 | -9 | 40 |
Step 2.7
All numbers except the last become the coefficients of the quotient polynomial. The last value in the result line is the remainder.
(1)x-9+40x+4
Step 2.8
Simplify the quotient polynomial.
x-9+40x+4
x-9+40x+4
Step 3
The remainder of the synthetic division is the result based on the remainder theorem.
40
Step 4
Since the remainder is not equal to zero, x=-4 is not a factor.
x=-4 is not a factor
Step 5