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Let f(x) = 4x^(2)-4ax+a^(2)-2a+2 and the...

Let f(x) = `4x^(2)-4ax+a^(2)-2a+2` and the golbal minimum value of f(x) for x in [0,2] is equal to 3
The number of values of a for which the global minimum value equal to 3 for x in [0,2] occurs at the endpoint of interval[0,2] is

A

1

B

2

C

3

D

0

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To solve the problem, we are given the function: \[ f(x) = 4x^2 - 4ax + (a^2 - 2a + 2) \] We need to find the number of values of \( a \) such that the global minimum of \( f(x) \) on the interval \([0, 2]\) is equal to 3, and this minimum occurs at one of the endpoints (either \( x = 0 \) or \( x = 2 \)). ### Step 1: Evaluate \( f(0) \) and \( f(2) \) First, we calculate the function values at the endpoints: 1. **At \( x = 0 \)**: \[ f(0) = 4(0)^2 - 4a(0) + (a^2 - 2a + 2) = a^2 - 2a + 2 \] 2. **At \( x = 2 \)**: \[ f(2) = 4(2)^2 - 4a(2) + (a^2 - 2a + 2) = 16 - 8a + a^2 - 2a + 2 = a^2 - 10a + 18 \] ### Step 2: Set up equations for the global minimum We need to find conditions under which either \( f(0) = 3 \) or \( f(2) = 3 \). 1. **Condition 1: \( f(0) = 3 \)**: \[ a^2 - 2a + 2 = 3 \implies a^2 - 2a - 1 = 0 \] Using the quadratic formula: \[ a = \frac{2 \pm \sqrt{(-2)^2 - 4 \cdot 1 \cdot (-1)}}{2 \cdot 1} = \frac{2 \pm \sqrt{4 + 4}}{2} = \frac{2 \pm 2\sqrt{2}}{2} = 1 \pm \sqrt{2} \] 2. **Condition 2: \( f(2) = 3 \)**: \[ a^2 - 10a + 18 = 3 \implies a^2 - 10a + 15 = 0 \] Using the quadratic formula: \[ a = \frac{10 \pm \sqrt{(-10)^2 - 4 \cdot 1 \cdot 15}}{2 \cdot 1} = \frac{10 \pm \sqrt{100 - 60}}{2} = \frac{10 \pm \sqrt{40}}{2} = \frac{10 \pm 2\sqrt{10}}{2} = 5 \pm \sqrt{10} \] ### Step 3: Count the valid values of \( a \) From the calculations, we have: - From \( f(0) = 3 \): \( a = 1 + \sqrt{2} \) and \( a = 1 - \sqrt{2} \) - From \( f(2) = 3 \): \( a = 5 + \sqrt{10} \) and \( a = 5 - \sqrt{10} \) ### Step 4: Check if the minimum occurs at the endpoints 1. **For \( a = 1 + \sqrt{2} \)**: - Check if \( a/2 \) lies in \([0, 2]\): \[ \frac{1 + \sqrt{2}}{2} \approx 1.207 \quad (\text{valid}) \] 2. **For \( a = 1 - \sqrt{2} \)**: - Check if \( a/2 \) lies in \([0, 2]\): \[ \frac{1 - \sqrt{2}}{2} < 0 \quad (\text{not valid}) \] 3. **For \( a = 5 + \sqrt{10} \)**: - Check if \( a/2 \) lies in \([0, 2]\): \[ \frac{5 + \sqrt{10}}{2} > 2 \quad (\text{not valid}) \] 4. **For \( a = 5 - \sqrt{10} \)**: - Check if \( a/2 \) lies in \([0, 2]\): \[ \frac{5 - \sqrt{10}}{2} \approx 1.43 \quad (\text{valid}) \] ### Conclusion The valid values of \( a \) for which the global minimum occurs at the endpoints are: 1. \( a = 1 + \sqrt{2} \) 2. \( a = 5 - \sqrt{10} \) Thus, the total number of values of \( a \) is **2**.

To solve the problem, we are given the function: \[ f(x) = 4x^2 - 4ax + (a^2 - 2a + 2) \] We need to find the number of values of \( a \) such that the global minimum of \( f(x) \) on the interval \([0, 2]\) is equal to 3, and this minimum occurs at one of the endpoints (either \( x = 0 \) or \( x = 2 \)). ### Step 1: Evaluate \( f(0) \) and \( f(2) \) ...
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