Determining if (x-2) is a factor of x^4 + 2x^3 - 7x^2 - 8x + 12
In algebra, a factor of a polynomial is a polynomial that divides evenly into the original polynomial. We can use the Factor Theorem to determine if a binomial of the form (x-a) is a factor of a polynomial.
The Factor Theorem: A binomial (x-a) is a factor of a polynomial p(x) if and only if p(a) = 0.
Let's apply this to our problem:
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Identify 'a': In our binomial (x-2), a = 2.
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Substitute 'a' into the polynomial: We need to find the value of the polynomial when x = 2:
- p(2) = (2)^4 + 2(2)^3 - 7(2)^2 - 8(2) + 12
- p(2) = 16 + 16 - 28 - 16 + 12
- p(2) = 0
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Interpret the result: Since p(2) = 0, the Factor Theorem tells us that (x-2) is indeed a factor of the polynomial x^4 + 2x^3 - 7x^2 - 8x + 12.
Further Exploration:
- We can use polynomial long division or synthetic division to divide the polynomial by (x-2) and obtain the quotient, which will be another factor of the original polynomial.
- This process can be repeated to factor the polynomial completely.