Warm up Divide
Synthetic division can be used when the divisor is in the form  (x – k). Example:  Use synthetic division for the following   (2x 3 – 7x 2 – 8x + 16) ÷ (x – 4) First, write down the coefficients in descending order, and  k  of the divisor in the form  x – k  : 4  2  –7  –8   16 k 2 Bring down the first coefficient. 8 Multiply this by  k 1 Add the column. 4 – 4 – 16 0 These are the coefficients of the quotient (and the remainder) 2x 2   + x – 4 Repeat the  process.
Example:  Divide (5x 3  + x 2  – 7) ÷ (x + 1) –1  5  1  0   –7 Notice that k  is –1 since synthetic division works for divisors in the form (x – k). place-holder 5x 2  – 4x + 4 –  11    x + 1 5 – 5 – 4 4 4 – 4 – 11
You Try:  Divide  (3x 4  + 12x 3  – 5x 2  – 18x + 8) ÷ (x + 4) –4  3  12  –5  –18  8 3x 3  – 5x – 2 3 – 12 0 0 – 5 20 2 – 8 0

Synthetic Division

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    Synthetic division canbe used when the divisor is in the form (x – k). Example: Use synthetic division for the following (2x 3 – 7x 2 – 8x + 16) ÷ (x – 4) First, write down the coefficients in descending order, and k of the divisor in the form x – k : 4 2 –7 –8 16 k 2 Bring down the first coefficient. 8 Multiply this by k 1 Add the column. 4 – 4 – 16 0 These are the coefficients of the quotient (and the remainder) 2x 2 + x – 4 Repeat the process.
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    Example: Divide(5x 3 + x 2 – 7) ÷ (x + 1) –1 5 1 0 –7 Notice that k is –1 since synthetic division works for divisors in the form (x – k). place-holder 5x 2 – 4x + 4 – 11 x + 1 5 – 5 – 4 4 4 – 4 – 11
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    You Try: Divide (3x 4 + 12x 3 – 5x 2 – 18x + 8) ÷ (x + 4) –4 3 12 –5 –18 8 3x 3 – 5x – 2 3 – 12 0 0 – 5 20 2 – 8 0