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Consider the polynomial f(x)=a x^2+b x+c...

Consider the polynomial `f(x)=a x^2+b x+cdot` If `f(0),f(2)=2,` then the minimum value of `int_0^2|f^(prime)(x)dxi s___`

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To solve the problem, we need to find the minimum value of the integral \( \int_0^2 |f'(x)| \, dx \) given that \( f(0) = 0 \) and \( f(2) = 2 \) for the polynomial \( f(x) = ax^2 + bx + c \). ### Step-by-Step Solution: 1. **Define the Polynomial**: The polynomial is given as: \[ f(x) = ax^2 + bx + c \] 2. **Use the Conditions**: We know: - \( f(0) = c = 0 \) - \( f(2) = 4a + 2b + c = 2 \) Since \( c = 0 \), we can simplify the second condition: \[ 4a + 2b = 2 \] This can be rewritten as: \[ 2a + b = 1 \quad \text{(Equation 1)} \] 3. **Find the Derivative**: The derivative of the polynomial is: \[ f'(x) = 2ax + b \] 4. **Set Up the Integral**: We need to evaluate: \[ \int_0^2 |f'(x)| \, dx = \int_0^2 |2ax + b| \, dx \] 5. **Determine Where \( f'(x) \) Changes Sign**: To find where \( f'(x) = 0 \): \[ 2ax + b = 0 \implies x = -\frac{b}{2a} \] We need to check if this point lies within the interval \([0, 2]\). 6. **Evaluate the Integral**: Depending on the sign of \( a \): - If \( a > 0 \), \( f'(x) \) is increasing, and we evaluate the integral based on whether \( -\frac{b}{2a} \) is in \([0, 2]\). - If \( a < 0 \), \( f'(x) \) is decreasing. For simplicity, let's assume \( a = 0 \) (linear case): \[ f'(x) = b \] Then: \[ \int_0^2 |b| \, dx = 2|b| \] 7. **Using Equation 1**: From Equation 1, we have \( b = 1 - 2a \). Thus: \[ 2|b| = 2|1 - 2a| \] 8. **Minimize the Integral**: To minimize \( 2|1 - 2a| \), we find the value of \( a \) that makes \( 1 - 2a = 0 \): \[ 1 - 2a = 0 \implies a = \frac{1}{2} \] Substituting \( a = \frac{1}{2} \) into Equation 1 gives: \[ b = 1 - 2 \cdot \frac{1}{2} = 0 \] 9. **Final Evaluation**: Thus, substituting \( a \) and \( b \) back, we find: \[ \int_0^2 |f'(x)| \, dx = 2|0| = 0 \] However, since we need \( f(2) = 2 \), we find that the minimum value of the integral is actually: \[ \int_0^2 |f'(x)| \, dx \geq 2 \] ### Conclusion: The minimum value of \( \int_0^2 |f'(x)| \, dx \) is: \[ \boxed{2} \]

To solve the problem, we need to find the minimum value of the integral \( \int_0^2 |f'(x)| \, dx \) given that \( f(0) = 0 \) and \( f(2) = 2 \) for the polynomial \( f(x) = ax^2 + bx + c \). ### Step-by-Step Solution: 1. **Define the Polynomial**: The polynomial is given as: \[ f(x) = ax^2 + bx + c ...
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