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Check whether the Lagrange formula is ap...

Check whether the Lagrange formula is applicable to following functions
`f(x) = 4x^(3) - 5x^(2) +x-2 " on " [0,1]`

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To check whether Lagrange's Mean Value Theorem (LMVT) is applicable to the function \( f(x) = 4x^3 - 5x^2 + x - 2 \) on the interval \([0, 1]\), we need to follow these steps: ### Step 1: Check Continuity The first condition for applying LMVT is that the function must be continuous on the closed interval \([a, b]\). **Solution:** Since \( f(x) \) is a polynomial function, it is continuous everywhere, including the interval \([0, 1]\). ### Step 2: Check Differentiability The second condition is that the function must be differentiable on the open interval \((a, b)\). **Solution:** Again, since \( f(x) \) is a polynomial function, it is differentiable everywhere, including the interval \((0, 1)\). ### Step 3: Apply Lagrange's Mean Value Theorem Since both conditions are satisfied, we can apply LMVT. According to LMVT, there exists at least one point \( c \) in the interval \((0, 1)\) such that: \[ f'(c) = \frac{f(b) - f(a)}{b - a} \] where \( a = 0 \) and \( b = 1 \). **Solution:** First, we calculate \( f(0) \) and \( f(1) \): \[ f(0) = 4(0)^3 - 5(0)^2 + 0 - 2 = -2 \] \[ f(1) = 4(1)^3 - 5(1)^2 + 1 - 2 = 4 - 5 + 1 - 2 = -2 \] Now, substituting these values into the LMVT formula: \[ f'(c) = \frac{f(1) - f(0)}{1 - 0} = \frac{-2 - (-2)}{1 - 0} = \frac{0}{1} = 0 \] ### Step 4: Find \( f'(x) \) Next, we need to find the derivative \( f'(x) \): **Solution:** \[ f'(x) = \frac{d}{dx}(4x^3 - 5x^2 + x - 2) = 12x^2 - 10x + 1 \] ### Step 5: Set \( f'(c) = 0 \) Now, we set \( f'(c) = 0 \): \[ 12c^2 - 10c + 1 = 0 \] ### Step 6: Solve the Quadratic Equation To find the value of \( c \), we can use the quadratic formula: \[ c = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Here, \( a = 12 \), \( b = -10 \), and \( c = 1 \). **Solution:** \[ c = \frac{10 \pm \sqrt{(-10)^2 - 4 \cdot 12 \cdot 1}}{2 \cdot 12} \] \[ = \frac{10 \pm \sqrt{100 - 48}}{24} \] \[ = \frac{10 \pm \sqrt{52}}{24} \] \[ = \frac{10 \pm 2\sqrt{13}}{24} = \frac{5 \pm \sqrt{13}}{12} \] ### Conclusion Since we have found values of \( c \) in the interval \((0, 1)\), we conclude that Lagrange's Mean Value Theorem is applicable to the function \( f(x) = 4x^3 - 5x^2 + x - 2 \) on the interval \([0, 1]\). ---
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