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"If " int(2cosx-sinx+lambda)/(cosx+sinx-...

`"If " int(2cosx-sinx+lambda)/(cosx+sinx-2)dx=A " In"|cosx+sinx-2|+Bx+C, " then the value of " A+B+|lambda| " is"-.`

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To solve the integral problem given, we need to find the values of \( A \), \( B \), and \( \lambda \) from the equation: \[ \int \frac{2\cos x - \sin x + \lambda}{\cos x + \sin x - 2} \, dx = A \ln |\cos x + \sin x - 2| + Bx + C \] ### Step 1: Set up the integral Let: \[ I = \int \frac{2\cos x - \sin x + \lambda}{\cos x + \sin x - 2} \, dx \] ### Step 2: Differentiate both sides Differentiate both sides with respect to \( x \): \[ \frac{dI}{dx} = \frac{2\cos x - \sin x + \lambda}{\cos x + \sin x - 2} \] For the right-hand side, we differentiate: \[ \frac{d}{dx} \left( A \ln |\cos x + \sin x - 2| + Bx + C \right) \] Using the chain rule: \[ = A \cdot \frac{1}{\cos x + \sin x - 2} \cdot \frac{d}{dx}(\cos x + \sin x - 2) + B \] \[ = A \cdot \frac{1}{\cos x + \sin x - 2} \cdot (-\sin x + \cos x) + B \] ### Step 3: Set the derivatives equal Now we equate both sides: \[ \frac{2\cos x - \sin x + \lambda}{\cos x + \sin x - 2} = A \cdot \frac{-\sin x + \cos x}{\cos x + \sin x - 2} + B \] ### Step 4: Clear the denominator Multiply through by \( \cos x + \sin x - 2 \): \[ 2\cos x - \sin x + \lambda = A(-\sin x + \cos x) + B(\cos x + \sin x - 2) \] ### Step 5: Expand the right-hand side Expanding the right-hand side gives: \[ 2\cos x - \sin x + \lambda = A\cos x - A\sin x + B\cos x + B\sin x - 2B \] \[ = (A + B)\cos x + (-A + B)\sin x - 2B \] ### Step 6: Compare coefficients Now we can compare coefficients on both sides: 1. Coefficient of \( \cos x \): \[ 2 = A + B \quad \text{(1)} \] 2. Coefficient of \( \sin x \): \[ -1 = -A + B \quad \text{(2)} \] 3. Constant term: \[ \lambda = -2B \quad \text{(3)} \] ### Step 7: Solve the system of equations From equation (1): \[ B = 2 - A \] Substituting \( B \) into equation (2): \[ -1 = -A + (2 - A) \] \[ -1 = 2 - 2A \] \[ 2A = 3 \quad \Rightarrow \quad A = \frac{3}{2} \] Now substituting \( A \) back into equation (1): \[ 2 = \frac{3}{2} + B \quad \Rightarrow \quad B = 2 - \frac{3}{2} = \frac{1}{2} \] Now substituting \( B \) into equation (3): \[ \lambda = -2 \cdot \frac{1}{2} = -1 \] ### Step 8: Calculate \( A + B + |\lambda| \) Now we can find \( A + B + |\lambda| \): \[ A + B + |\lambda| = \frac{3}{2} + \frac{1}{2} + 1 = 2 + 1 = 3 \] Thus, the final answer is: \[ \boxed{3} \]

To solve the integral problem given, we need to find the values of \( A \), \( B \), and \( \lambda \) from the equation: \[ \int \frac{2\cos x - \sin x + \lambda}{\cos x + \sin x - 2} \, dx = A \ln |\cos x + \sin x - 2| + Bx + C \] ### Step 1: Set up the integral Let: ...
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