Polynomial Long Division: (x⁴+4x³+16x−35) ÷ (x+5)
This article will guide you through the process of performing polynomial long division to solve the problem: (x⁴+4x³+16x−35) ÷ (x+5)
Understanding Polynomial Long Division
Polynomial long division is a method for dividing polynomials, similar to long division with numbers. It helps us find the quotient and remainder when dividing one polynomial by another.
Steps for Polynomial Long Division
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Set up the division:
- Write the dividend (x⁴+4x³+16x−35) inside the division symbol.
- Write the divisor (x+5) outside the division symbol.
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Divide the leading terms:
- Divide the leading term of the dividend (x⁴) by the leading term of the divisor (x). This gives us x³.
- Write x³ above the division symbol, aligning it with the x⁴ term.
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Multiply the quotient by the divisor:
- Multiply x³ by the entire divisor (x+5). This gives us x⁴ + 5x³.
- Write the result below the dividend, aligning like terms.
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Subtract:
- Subtract the result (x⁴ + 5x³) from the dividend.
- This leaves us with -x³ + 16x - 35.
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Bring down the next term:
- Bring down the next term of the dividend (16x).
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Repeat steps 2-5:
- Divide the new leading term (-x³) by the leading term of the divisor (x). This gives us -x².
- Write -x² above the division symbol, aligning it with the x³ term.
- Multiply -x² by the divisor (x+5), giving us -x³ - 5x².
- Subtract this result from the current expression.
- Bring down the next term (-35).
- Continue this process until the degree of the remainder is less than the degree of the divisor.
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Write the answer:
- The quotient is the polynomial above the division symbol.
- The remainder is the last term in the division.
Applying the Steps
Let's apply these steps to our problem:
x³ - x² + 5x - 9
______________________
x+5 | x⁴ + 4x³ + 16x - 35
-(x⁴ + 5x³)
-----------------
-x³ + 16x
-(-x³ - 5x²)
-----------------
5x² + 16x
-(5x² + 25x)
-----------------
-9x - 35
-(-9x - 45)
-----------------
10
Conclusion
Therefore, (x⁴+4x³+16x−35) ÷ (x+5) = x³ - x² + 5x - 9 + 10/(x+5)
The quotient is x³ - x² + 5x - 9 and the remainder is 10. This result can be expressed as:
- Quotient + Remainder / Divisor
x³ - x² + 5x - 9 + 10/(x+5)