Factoring and Solving (x-1)^2 - 4
The expression (x-1)^2 - 4 is a quadratic expression that can be factored and solved for its roots. Let's break down the process:
Factoring the Expression
- Recognize the pattern: The expression is in the form of a² - b², which is a difference of squares pattern.
- Apply the difference of squares formula: a² - b² = (a + b)(a - b)
- Substitute: In our case, a = (x-1) and b = 2.
- Factor: (x-1)² - 4 = ((x-1) + 2)((x-1) - 2)
- Simplify: (x-1)² - 4 = (x+1)(x-3)
Solving for the Roots
To find the roots, we set the factored expression equal to zero and solve for x:
(x+1)(x-3) = 0
This gives us two possible solutions:
- x + 1 = 0 => x = -1
- x - 3 = 0 => x = 3
Summary
Therefore, the factored form of (x-1)² - 4 is (x+1)(x-3). The roots of the expression are x = -1 and x = 3.
This demonstrates how recognizing common algebraic patterns like the difference of squares can simplify factoring and solving quadratic expressions.