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(i) int (e^(x) .(1-x))/(x^(2))dx (ii) ...

`(i) int (e^(x) .(1-x))/(x^(2))dx`
`(ii) int ((1+sin x)/(1+cos x))e^(x) dx`

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Let's solve the given integrals step by step. ### Part (i): Evaluate the integral \[ I_1 = \int \frac{e^x (1 - x)}{x^2} \, dx \] **Step 1: Split the integral** We can separate the integrand: \[ I_1 = \int \left( \frac{e^x}{x^2} - \frac{e^x x}{x^2} \right) \, dx = \int \frac{e^x}{x^2} \, dx - \int \frac{e^x}{x} \, dx \] **Step 2: Recognize the forms** The integrals \(\int \frac{e^x}{x^2} \, dx\) and \(\int \frac{e^x}{x} \, dx\) can be solved using integration by parts or known results. **Step 3: Integration by parts** Let’s use integration by parts for both integrals. For the first integral, let: - \(u = \frac{1}{x}\) and \(dv = e^x dx\) - Then \(du = -\frac{1}{x^2} dx\) and \(v = e^x\) Using integration by parts: \[ \int \frac{e^x}{x^2} \, dx = \frac{e^x}{x} - \int e^x \left(-\frac{1}{x^2}\right) dx = \frac{e^x}{x} + \int \frac{e^x}{x^2} \, dx \] This leads to a recursive relation. **Step 4: Solve the recursive relation** We can denote: \[ I = \int \frac{e^x}{x^2} \, dx \] Then: \[ I = \frac{e^x}{x} + I \] This implies: \[ I = \frac{e^x}{x} + C \] **Step 5: Combine results** Thus: \[ I_1 = \left( \frac{e^x}{x} + C_1 \right) - \left( e^x \ln |x| + C_2 \right) \] The final result is: \[ I_1 = \frac{e^x}{x} - e^x \ln |x| + C \] ### Part (ii): Evaluate the integral \[ I_2 = \int \frac{1 + \sin x}{1 + \cos x} e^x \, dx \] **Step 1: Simplify the integrand** We can rewrite: \[ \frac{1 + \sin x}{1 + \cos x} = \frac{(1 + \cos x) + \sin x - \cos x}{1 + \cos x} = 1 + \frac{\sin x - \cos x}{1 + \cos x} \] Thus: \[ I_2 = \int e^x \, dx + \int \frac{(\sin x - \cos x)e^x}{1 + \cos x} \, dx \] **Step 2: Solve the first integral** The first integral is straightforward: \[ \int e^x \, dx = e^x + C \] **Step 3: Solve the second integral** For the second part, we can use integration by parts again. Let: - \(u = \frac{\sin x - \cos x}{1 + \cos x}\) and \(dv = e^x dx\) - Then \(du\) and \(v\) can be calculated accordingly. Using integration by parts: \[ \int u \, dv = uv - \int v \, du \] **Step 4: Combine results** After solving, we will have: \[ I_2 = e^x + \text{(result from the second integral)} + C \] ### Final Answers: 1. \(I_1 = \frac{e^x}{x} - e^x \ln |x| + C\) 2. \(I_2 = e^x + \text{(result from the second integral)} + C\)
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