Solving the Equation: (x-1)^3-(x+3)(x^2-3x+9)+3(x^2-4)=2
This article will guide you through the process of solving the equation (x-1)^3-(x+3)(x^2-3x+9)+3(x^2-4)=2. We will break down the problem step-by-step, simplifying the expression and arriving at the solution.
Expanding and Simplifying
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Expand the cubes: We begin by expanding the cube term using the formula (a-b)^3 = a^3 - 3a^2b + 3ab^2 - b^3.
(x-1)^3 = x^3 - 3x^2 + 3x - 1
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Expand the product: The expression (x+3)(x^2-3x+9) is a product of the sum and difference of two cubes. We can use the formula (a+b)(a^2-ab+b^2) = a^3 + b^3 to simplify.
(x+3)(x^2-3x+9) = x^3 + 3^3 = x^3 + 27
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Simplify the expression: Substitute the expanded forms back into the original equation:
(x^3 - 3x^2 + 3x - 1) - (x^3 + 27) + 3(x^2 - 4) = 2
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Combine like terms: Remove the parentheses and combine the terms with similar powers of x.
x^3 - 3x^2 + 3x - 1 - x^3 - 27 + 3x^2 - 12 = 2
3x - 40 = 2
Solving for x
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Isolate the x term: Add 40 to both sides of the equation.
3x = 42
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Solve for x: Divide both sides by 3.
x = 14
Conclusion
Therefore, the solution to the equation (x-1)^3-(x+3)(x^2-3x+9)+3(x^2-4)=2 is x = 14.