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Solve the equations: Q. x(x-1)(x+2)(x-...

Solve the equations:
Q. `x(x-1)(x+2)(x-3)+8=0`.

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To solve the equation \( x(x-1)(x+2)(x-3) + 8 = 0 \), we will follow these steps: ### Step 1: Expand the equation First, we need to expand the product \( x(x-1)(x+2)(x-3) \). 1. Multiply the first two factors: \[ x(x-1) = x^2 - x \] 2. Multiply the last two factors: \[ (x+2)(x-3) = x^2 - 3x + 2x - 6 = x^2 - x - 6 \] 3. Now, multiply the results from the first two steps: \[ (x^2 - x)(x^2 - x - 6) = x^2(x^2 - x - 6) - x(x^2 - x - 6) \] Expanding this gives: \[ = x^4 - x^3 - 6x^2 - (x^3 - x^2 + 6x) = x^4 - 2x^3 - 5x^2 + 6x \] 4. Now, add 8 to the equation: \[ x^4 - 2x^3 - 5x^2 + 6x + 8 = 0 \] ### Step 2: Factor the polynomial Next, we will try to find rational roots using the Rational Root Theorem. We can test \( x = -1 \): 1. Substitute \( x = -1 \): \[ (-1)^4 - 2(-1)^3 - 5(-1)^2 + 6(-1) + 8 = 1 + 2 - 5 - 6 + 8 = 0 \] Since this equals zero, \( x + 1 \) is a factor. ### Step 3: Perform polynomial long division Now, we will divide \( x^4 - 2x^3 - 5x^2 + 6x + 8 \) by \( x + 1 \): 1. Divide \( x^4 \) by \( x \) to get \( x^3 \). 2. Multiply \( x^3 \) by \( x + 1 \) to get \( x^4 + x^3 \). 3. Subtract this from the original polynomial: \[ (-2x^3 - x^3) = -3x^3 \] 4. Bring down the next term: \[ -3x^3 - 5x^2 + 6x + 8 \] 5. Repeat this process until you get the quotient: \[ x^3 - 3x^2 - 2x + 8 \] ### Step 4: Find the roots of the cubic polynomial Now we need to solve \( x^3 - 3x^2 - 2x + 8 = 0 \). We can test \( x = 2 \): 1. Substitute \( x = 2 \): \[ 2^3 - 3(2^2) - 2(2) + 8 = 8 - 12 - 4 + 8 = 0 \] So, \( x - 2 \) is another factor. ### Step 5: Perform polynomial long division again Now divide \( x^3 - 3x^2 - 2x + 8 \) by \( x - 2 \): 1. Divide \( x^3 \) by \( x \) to get \( x^2 \). 2. Multiply \( x^2 \) by \( x - 2 \) to get \( x^3 - 2x^2 \). 3. Subtract: \[ (-3x^2 + 2x^2) = -x^2 \] 4. Bring down the next term: \[ -x^2 - 2x + 8 \] 5. Repeat this process until you get: \[ x^2 - x - 4 \] ### Step 6: Solve the quadratic equation Now we need to solve \( x^2 - x - 4 = 0 \) using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Where \( a = 1, b = -1, c = -4 \): \[ x = \frac{1 \pm \sqrt{(-1)^2 - 4(1)(-4)}}{2(1)} = \frac{1 \pm \sqrt{1 + 16}}{2} = \frac{1 \pm \sqrt{17}}{2} \] ### Final solutions The solutions to the original equation are: 1. \( x = -1 \) 2. \( x = 2 \) 3. \( x = \frac{1 + \sqrt{17}}{2} \) 4. \( x = \frac{1 - \sqrt{17}}{2} \)
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