Synthetic Division: (x⁴−5x³−8x² +13x−12) ÷ (x−6)
Synthetic division is a shorthand method for dividing polynomials, particularly when the divisor is a linear expression in the form (x - a). Let's break down how to use synthetic division to solve the problem (x⁴−5x³−8x² +13x−12) ÷ (x−6).
Step 1: Setting up the problem
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Identify the coefficients: Write down the coefficients of the dividend polynomial, ensuring to include a coefficient of 0 for any missing terms in the descending order of powers:
1 -5 -8 13 -12
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Identify the divisor: The divisor is (x - 6). Take the opposite of the constant term, which is 6.
Step 2: Performing the division
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Bring down the first coefficient: Bring down the first coefficient, 1, below the line.
6 | 1 -5 -8 13 -12 -------------------- 1
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Multiply and add: Multiply the number you just brought down (1) by the divisor (6) and place the product (6) under the next coefficient (-5). Add the two numbers together (-5 + 6 = 1) and write the result below the line.
6 | 1 -5 -8 13 -12 -------------------- 1 1
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Repeat: Continue this process, multiplying the number you just wrote below the line (1) by the divisor (6) and adding it to the next coefficient (-8).
6 | 1 -5 -8 13 -12 -------------------- 1 1 2
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Continue until you reach the last coefficient: Repeat the process until you reach the last coefficient.
6 | 1 -5 -8 13 -12 -------------------- 1 1 2 25
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The remainder: The last number below the line is the remainder.
6 | 1 -5 -8 13 -12 -------------------- 1 1 2 25 98
Step 3: Interpreting the result
The numbers below the line represent the coefficients of the quotient polynomial, starting from the highest degree:
- Quotient: x³ + x² + 2x + 25
- Remainder: 98
Therefore, (x⁴−5x³−8x² +13x−12) ÷ (x−6) = x³ + x² + 2x + 25 + 98/(x-6)