Dividing Polynomials: (2x^3 - 3x^2 + 5x - 1) / (x + 2)
This article will guide you through the process of dividing the polynomial 2x^3 - 3x^2 + 5x - 1 by the binomial x + 2. We'll use polynomial long division to achieve this.
Understanding Polynomial Long Division
Polynomial long division is very similar to regular long division with numbers. Here's a breakdown:
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Set up the division:
- Write the dividend (the polynomial being divided) inside the division symbol.
- Write the divisor (the polynomial dividing) outside the division symbol.
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Focus on the leading terms:
- Divide the leading term of the dividend by the leading term of the divisor.
- Write the result above the dividend.
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Multiply and subtract:
- Multiply the result from step 2 by the entire divisor.
- Subtract the result from the dividend.
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Bring down the next term:
- Bring down the next term from the dividend.
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Repeat steps 2-4:
- Repeat the process until there are no more terms in the dividend.
Performing the Division
Let's apply these steps to our problem:
2x^2 - 7x + 19
x + 2 | 2x^3 - 3x^2 + 5x - 1
-(2x^3 + 4x^2)
------------------
-7x^2 + 5x
-(-7x^2 - 14x)
------------------
19x - 1
-(19x + 38)
---------------
-39
Interpreting the Result
The result of the division is:
- Quotient: 2x^2 - 7x + 19
- Remainder: -39
This can be written as:
(2x^3 - 3x^2 + 5x - 1) / (x + 2) = 2x^2 - 7x + 19 - 39/(x + 2)
In simpler terms, this means that the polynomial 2x^3 - 3x^2 + 5x - 1 can be expressed as (x + 2) multiplied by 2x^2 - 7x + 19, with a remainder of -39.
Conclusion
Polynomial long division is a powerful tool for dividing polynomials. By following these steps, you can successfully divide any polynomial by another polynomial.