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Solve : (i) |x^(2)-2x|le x , (ii) (x^(...

Solve :
`(i) |x^(2)-2x|le x` , `(ii) (x^(2)-9)(|x|-2)le0`

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To solve the given inequalities step by step, we will break down each part of the question. ### (i) Solve the inequality: \(|x^2 - 2x| \leq x\) **Step 1: Remove the absolute value.** The expression \(|x^2 - 2x| \leq x\) can be split into two cases: 1. \(x^2 - 2x \leq x\) 2. \(-(x^2 - 2x) \leq x\) or \(x^2 - 2x \geq -x\) **Step 2: Solve the first case.** From \(x^2 - 2x \leq x\): \[ x^2 - 3x \leq 0 \] Factoring gives: \[ x(x - 3) \leq 0 \] The critical points are \(x = 0\) and \(x = 3\). We test intervals: - For \(x < 0\) (e.g., \(x = -1\)): \((-1)(-4) > 0\) (not satisfied) - For \(0 < x < 3\) (e.g., \(x = 1\)): \((1)(-2) < 0\) (satisfied) - For \(x > 3\) (e.g., \(x = 4\)): \((4)(1) > 0\) (not satisfied) Thus, the solution from this case is: \[ 0 \leq x \leq 3 \] **Step 3: Solve the second case.** From \(x^2 - 2x \geq -x\): \[ x^2 - x \geq 0 \] Factoring gives: \[ x(x - 1) \geq 0 \] The critical points are \(x = 0\) and \(x = 1\). We test intervals: - For \(x < 0\) (e.g., \(x = -1\)): \((-1)(-2) > 0\) (not satisfied) - For \(0 < x < 1\) (e.g., \(x = 0.5\)): \((0.5)(-0.5) < 0\) (not satisfied) - For \(x > 1\) (e.g., \(x = 2\)): \((2)(1) > 0\) (satisfied) Thus, the solution from this case is: \[ x \geq 1 \] **Step 4: Combine the solutions.** From the first case, we have \(0 \leq x \leq 3\) and from the second case \(x \geq 1\). The combined solution is: \[ 1 \leq x \leq 3 \] ### (ii) Solve the inequality: \((x^2 - 9)(|x| - 2) \leq 0\) **Step 1: Identify critical points.** The critical points occur when \(x^2 - 9 = 0\) and \(|x| - 2 = 0\): 1. \(x^2 - 9 = 0 \Rightarrow x = 3, -3\) 2. \(|x| - 2 = 0 \Rightarrow x = 2, -2\) Thus, the critical points are \(-3, -2, 2, 3\). **Step 2: Test intervals.** We will test the intervals defined by these critical points: \((-∞, -3)\), \((-3, -2)\), \((-2, 2)\), \((2, 3)\), and \((3, ∞)\). - For \(x < -3\) (e.g., \(x = -4\)): \[ (-4^2 - 9)(|-4| - 2) = (16 - 9)(4 - 2) = 7 \cdot 2 > 0 \quad \text{(not satisfied)} \] - For \(-3 < x < -2\) (e.g., \(x = -2.5\)): \[ ((-2.5)^2 - 9)(|-2.5| - 2) = (6.25 - 9)(2.5 - 2) = (-2.75)(0.5) < 0 \quad \text{(satisfied)} \] - For \(-2 < x < 2\) (e.g., \(x = 0\)): \[ (0^2 - 9)(|0| - 2) = (-9)(-2) > 0 \quad \text{(not satisfied)} \] - For \(2 < x < 3\) (e.g., \(x = 2.5\)): \[ ((2.5)^2 - 9)(|2.5| - 2) = (6.25 - 9)(2.5 - 2) = (-2.75)(0.5) < 0 \quad \text{(satisfied)} \] - For \(x > 3\) (e.g., \(x = 4\)): \[ (4^2 - 9)(|4| - 2) = (16 - 9)(4 - 2) = 7 \cdot 2 > 0 \quad \text{(not satisfied)} \] **Step 3: Include critical points.** The critical points where the expression equals zero are \(-3, -2, 2, 3\). Since the inequality is \(\leq 0\), we include these points. **Final Solution:** The solution to the inequality is: \[ [-3, -2] \cup [2, 3] \] ### Summary of Solutions: 1. For \(|x^2 - 2x| \leq x\): \(x \in [1, 3]\) 2. For \((x^2 - 9)(|x| - 2) \leq 0\): \(x \in [-3, -2] \cup [2, 3]\)
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