Expanding and Simplifying (x-2)(x+3)(x-7)
This article will guide you through the process of expanding and simplifying the expression (x-2)(x+3)(x-7) to its standard form.
Step 1: Multiply the first two factors
Begin by multiplying the first two factors: (x-2)(x+3). This can be done using the FOIL method (First, Outer, Inner, Last) or by distributing.
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FOIL:
- F: x * x = x²
- O: x * 3 = 3x
- I: -2 * x = -2x
- L: -2 * 3 = -6
- Combining the terms, we get: x² + 3x - 2x - 6 = x² + x - 6
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Distribution:
- x(x+3) - 2(x+3) = x² + 3x - 2x - 6 = x² + x - 6
Therefore, (x-2)(x+3) = x² + x - 6
Step 2: Multiply the result by the remaining factor
Now we have: (x² + x - 6)(x-7)
Again, we can use the distributive property or the FOIL method:
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Distribution:
- x²(x-7) + x(x-7) - 6(x-7) = x³ - 7x² + x² - 7x - 6x + 42
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FOIL:
- F: x² * x = x³
- O: x² * -7 = -7x²
- I: x * x = x²
- L: x * -7 = -7x
- F: -6 * x = -6x
- O: -6 * -7 = 42
- Combining the terms, we get: x³ - 7x² + x² - 7x - 6x + 42
Step 3: Combine like terms
Finally, combine the like terms in the resulting expression:
x³ - 7x² + x² - 7x - 6x + 42 = x³ - 6x² - 13x + 42
Conclusion
The standard form of the expression (x-2)(x+3)(x-7) is x³ - 6x² - 13x + 42.