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If 3x-x^2ge2 and y^2+yle2, then...

If 3x`-x^2ge2` and `y^2+yle2`, then

A

`-1lexyle2`

B

`-2lexyle2`

C

`-4lexyle4`

D

`-4lexyle2`

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The correct Answer is:
To solve the inequalities given in the question step by step, we will analyze each inequality separately and then find the relation between \(xy\). ### Step 1: Solve the first inequality \(3x - x^2 \geq 2\) 1. Rearrange the inequality: \[ 3x - x^2 - 2 \geq 0 \] This can be rewritten as: \[ -x^2 + 3x - 2 \geq 0 \] 2. Multiply through by -1 (remember to reverse the inequality): \[ x^2 - 3x + 2 \leq 0 \] 3. Factor the quadratic: \[ (x - 1)(x - 2) \leq 0 \] 4. Determine the intervals where this inequality holds: - The critical points are \(x = 1\) and \(x = 2\). - Test intervals: - For \(x < 1\), choose \(x = 0\): \((0 - 1)(0 - 2) = 2 > 0\) (not valid). - For \(1 < x < 2\), choose \(x = 1.5\): \((1.5 - 1)(1.5 - 2) = 0.5 \cdot -0.5 < 0\) (valid). - For \(x > 2\), choose \(x = 3\): \((3 - 1)(3 - 2) = 2 > 0\) (not valid). 5. Therefore, the solution for \(x\) is: \[ 1 \leq x \leq 2 \] ### Step 2: Solve the second inequality \(y^2 + y \leq 2\) 1. Rearrange the inequality: \[ y^2 + y - 2 \leq 0 \] 2. Factor the quadratic: \[ (y - 1)(y + 2) \leq 0 \] 3. Determine the intervals where this inequality holds: - The critical points are \(y = -2\) and \(y = 1\). - Test intervals: - For \(y < -2\), choose \(y = -3\): \((-3 - 1)(-3 + 2) = -4 < 0\) (valid). - For \(-2 < y < 1\), choose \(y = 0\): \((0 - 1)(0 + 2) = -2 < 0\) (valid). - For \(y > 1\), choose \(y = 2\): \((2 - 1)(2 + 2) = 4 > 0\) (not valid). 4. Therefore, the solution for \(y\) is: \[ -2 \leq y \leq 1 \] ### Step 3: Find the range of \(xy\) 1. The maximum value of \(x\) is \(2\) and the maximum value of \(y\) is \(1\). Thus: \[ \text{Maximum } xy = 2 \cdot 1 = 2 \] 2. The minimum value of \(y\) is \(-2\) and the minimum value of \(x\) is \(1\). Thus: \[ \text{Minimum } xy = 1 \cdot (-2) = -2 \] 3. The minimum value of \(xy\) when \(x = 2\) and \(y = -2\) is: \[ 2 \cdot (-2) = -4 \] ### Conclusion Thus, the range of \(xy\) is: \[ -4 \leq xy \leq 2 \]

To solve the inequalities given in the question step by step, we will analyze each inequality separately and then find the relation between \(xy\). ### Step 1: Solve the first inequality \(3x - x^2 \geq 2\) 1. Rearrange the inequality: \[ 3x - x^2 - 2 \geq 0 \] ...
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