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Using mean value theorem, prove that the...

Using mean value theorem, prove that there is a point on the curve `y = 2x^(2) - 5x+3` between the points `A(1,0)` and `B,(2,1)`, where tangent is parallel to the chord `AB`. Also, find that point.

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To solve the problem using the Mean Value Theorem (MVT), we need to follow these steps: ### Step 1: Verify the conditions of the Mean Value Theorem The Mean Value Theorem states that if a function \( f(x) \) is continuous on the closed interval \([a, b]\) and differentiable on the open interval \((a, b)\), then there exists at least one point \( c \) in \((a, b)\) such that: \[ f'(c) = \frac{f(b) - f(a)}{b - a} \] In our case, the function is \( f(x) = 2x^2 - 5x + 3 \), and we are considering the interval from \( A(1, 0) \) to \( B(2, 1) \). ### Step 2: Check continuity and differentiability The function \( f(x) = 2x^2 - 5x + 3 \) is a polynomial, which is continuous and differentiable everywhere. Therefore, it is continuous on \([1, 2]\) and differentiable on \((1, 2)\). ### Step 3: Calculate \( f(1) \) and \( f(2) \) Now we need to evaluate the function at the endpoints: \[ f(1) = 2(1)^2 - 5(1) + 3 = 2 - 5 + 3 = 0 \] \[ f(2) = 2(2)^2 - 5(2) + 3 = 8 - 10 + 3 = 1 \] ### Step 4: Apply the Mean Value Theorem Now, we can apply the MVT: \[ f'(c) = \frac{f(2) - f(1)}{2 - 1} = \frac{1 - 0}{1} = 1 \] ### Step 5: Find \( f'(x) \) Next, we find the derivative of \( f(x) \): \[ f'(x) = \frac{d}{dx}(2x^2 - 5x + 3) = 4x - 5 \] ### Step 6: Set \( f'(c) \) equal to 1 Now we set the derivative equal to 1: \[ 4c - 5 = 1 \] ### Step 7: Solve for \( c \) Solving for \( c \): \[ 4c = 6 \implies c = \frac{6}{4} = \frac{3}{2} \] ### Step 8: Find the corresponding \( y \)-coordinate Now we find the \( y \)-coordinate of the point on the curve at \( x = \frac{3}{2} \): \[ f\left(\frac{3}{2}\right) = 2\left(\frac{3}{2}\right)^2 - 5\left(\frac{3}{2}\right) + 3 \] Calculating this: \[ = 2 \cdot \frac{9}{4} - \frac{15}{2} + 3 = \frac{18}{4} - \frac{30}{4} + \frac{12}{4} = \frac{18 - 30 + 12}{4} = \frac{0}{4} = 0 \] ### Conclusion Thus, the point on the curve where the tangent is parallel to the chord \( AB \) is: \[ \left(\frac{3}{2}, 0\right) \]

To solve the problem using the Mean Value Theorem (MVT), we need to follow these steps: ### Step 1: Verify the conditions of the Mean Value Theorem The Mean Value Theorem states that if a function \( f(x) \) is continuous on the closed interval \([a, b]\) and differentiable on the open interval \((a, b)\), then there exists at least one point \( c \) in \((a, b)\) such that: \[ f'(c) = \frac{f(b) - f(a)}{b - a} \] ...
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