Simplifying the Expression (x-2)(x^2 + 2x + 4)
This expression involves multiplying a binomial (x-2) with a trinomial (x^2 + 2x + 4). We can simplify this using the distributive property (also known as FOIL method).
Understanding the Problem:
The expression represents the product of two factors:
- (x-2): This is a binomial, meaning it has two terms.
- (x^2 + 2x + 4): This is a trinomial, meaning it has three terms.
Simplifying the Expression:
To simplify this, we need to multiply each term in the binomial by each term in the trinomial:
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Multiply x (from the binomial) with each term in the trinomial:
- x * x^2 = x^3
- x * 2x = 2x^2
- x * 4 = 4x
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Multiply -2 (from the binomial) with each term in the trinomial:
- -2 * x^2 = -2x^2
- -2 * 2x = -4x
- -2 * 4 = -8
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Combine all the terms:
- x^3 + 2x^2 + 4x - 2x^2 - 4x - 8
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Simplify by combining like terms:
- x^3 + (2x^2 - 2x^2) + (4x - 4x) - 8
- x^3 - 8
Therefore, the simplified expression of (x-2)(x^2 + 2x + 4) is x^3 - 8.
Important Note: The trinomial (x^2 + 2x + 4) is a special case known as the "sum of cubes" pattern. This pattern can be factored as: (a^3 + b^3) = (a + b)(a^2 - ab + b^2)
In this case, a = x and b = 2, making the simplification a straightforward application of this pattern.