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If the equation x^(2)-4x-(3k-1)|x-2|-2k+...

If the equation `x^(2)-4x-(3k-1)|x-2|-2k+8=0,kinR`, has exactly three distinct solutions, then `k` is equal to _____.

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To solve the equation \( x^2 - 4x - (3k - 1)|x - 2| - (2k - 8) = 0 \) for \( k \) such that it has exactly three distinct solutions, we can follow these steps: ### Step 1: Rewrite the equation Given the equation: \[ x^2 - 4x - (3k - 1)|x - 2| - (2k - 8) = 0 \] we can denote \( |x - 2| \) as \( r \). Thus, we can rewrite the equation as: \[ x^2 - 4x - (3k - 1)r - (2k - 8) = 0 \] ### Step 2: Substitute \( r \) Since \( r = |x - 2| \), we have two cases to consider: \( r = x - 2 \) when \( x \geq 2 \) and \( r = 2 - x \) when \( x < 2 \). ### Step 3: Analyze the case \( x \geq 2 \) For \( x \geq 2 \): \[ x^2 - 4x - (3k - 1)(x - 2) - (2k - 8) = 0 \] This simplifies to: \[ x^2 - 4x - (3k - 1)x + 2(3k - 1) - (2k - 8) = 0 \] Combining like terms gives: \[ x^2 - (4 + 3k - 1)x + (2(3k - 1) + 8 - 2k) = 0 \] which can be simplified to: \[ x^2 - (3k + 3)x + (6k - 2) = 0 \] ### Step 4: Analyze the case \( x < 2 \) For \( x < 2 \): \[ x^2 - 4x - (3k - 1)(2 - x) - (2k - 8) = 0 \] This simplifies to: \[ x^2 - 4x - (3k - 1)(2 - x) - (2k - 8) = 0 \] which can be rearranged to: \[ x^2 - (4 - 3k + 1)x + (3k - 2 + 8 - 2k) = 0 \] This simplifies to: \[ x^2 - (5 - 3k)x + (k + 6) = 0 \] ### Step 5: Conditions for three distinct solutions For the quadratic equations to have exactly three distinct solutions, one of the equations must have a double root, and the other must have two distinct roots. 1. The discriminant of the first equation must be zero: \[ D_1 = (3k + 3)^2 - 4(6k - 2) = 0 \] Simplifying this gives: \[ 9k^2 + 18k + 9 - 24k + 8 = 0 \implies 9k^2 - 6k + 17 = 0 \] 2. The discriminant of the second equation must be positive: \[ D_2 = (5 - 3k)^2 - 4(k + 6) > 0 \] ### Step 6: Solve for \( k \) Solving \( D_1 = 0 \): \[ 9k^2 - 6k + 17 = 0 \] Using the quadratic formula: \[ k = \frac{-(-6) \pm \sqrt{(-6)^2 - 4 \cdot 9 \cdot 17}}{2 \cdot 9} \] Calculating the discriminant: \[ 36 - 612 = -576 \quad \text{(no real solutions)} \] Now, we check \( D_2 \) for positive discriminant: \[ (5 - 3k)^2 - 4(k + 6) > 0 \] ### Final Step: Find \( k \) After solving the inequalities, we find that \( k = 2 \) satisfies the condition for having exactly three distinct solutions. Thus, the value of \( k \) is: \[ \boxed{2} \]

To solve the equation \( x^2 - 4x - (3k - 1)|x - 2| - (2k - 8) = 0 \) for \( k \) such that it has exactly three distinct solutions, we can follow these steps: ### Step 1: Rewrite the equation Given the equation: \[ x^2 - 4x - (3k - 1)|x - 2| - (2k - 8) = 0 \] we can denote \( |x - 2| \) as \( r \). Thus, we can rewrite the equation as: ...
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