Simplifying the Expression (x+1)² - (x-1)² - 3(x+1)(x-1)
This article aims to simplify the given algebraic expression: (x+1)² - (x-1)² - 3(x+1)(x-1).
Understanding the Expression
The expression involves squaring binomials and multiplying them. We can use the following algebraic identities to simplify the expression:
- (a + b)² = a² + 2ab + b²
- (a - b)² = a² - 2ab + b²
- (a + b)(a - b) = a² - b²
Simplifying the Expression
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Expand the squares:
- (x+1)² = x² + 2x + 1
- (x-1)² = x² - 2x + 1
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Substitute the expanded forms into the original expression:
- (x² + 2x + 1) - (x² - 2x + 1) - 3(x+1)(x-1)
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Expand the last term using the difference of squares identity:
- (x² + 2x + 1) - (x² - 2x + 1) - 3(x² - 1)
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Distribute the negative sign and the constant 3:
- x² + 2x + 1 - x² + 2x - 1 - 3x² + 3
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Combine like terms:
- (x² - x² - 3x²) + (2x + 2x) + (1 - 1 + 3)
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Simplify:
- -3x² + 4x + 3
Conclusion
The simplified form of the expression (x+1)² - (x-1)² - 3(x+1)(x-1) is -3x² + 4x + 3. By using algebraic identities and carefully combining terms, we have successfully simplified the given expression.