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For a given differential equation edy/dx=x+1;x∈(−1,∞)e^{dy/dx} = x + 1; x \in (-1,\infty), then which of the following statements are TRUE?

(A) Its general solution is y=xlog⁡e(x+1)−x+log⁡e(x+1)+Cy = x\log_e(x+1) - x + \log_e(x+1) + C; C is an arbitrary constant.

(B) Its particular solution is y=(x+1)log⁡e(x+1)−x+5;y(0)=5y = (x+1)\log_e(x+1) - x + 5; y(0) = 5

(C) Its general solution is y=(x−1)log⁡(x+1)−x+Cy = (x-1)\log(x+1) - x + C; C is an arbitrary constant

(D) Its particular solution is y=(x−1)log⁡(x+1)−x+5;y(0)=5y = (x-1)\log(x+1) - x + 5; y(0) = 5

Choose the correct answer from the options given below:

Solution

✅ Correct Option: 3

Taking logarithms, dydx=log⁡e(x+1)\frac{dy}{dx}=\log_e(x+1).

Integrating by parts, y=(x+1)log⁡e(x+1)−(x+1)+Cy=(x+1)\log_e(x+1)-(x+1)+C, which absorbs the constant to y=(x+1)log⁡e(x+1)−x+Cy=(x+1)\log_e(x+1)-x+C. This is exactly statement (A) rewritten.

With y(0)=5y(0)=5: 0−0+C=50-0+C=5, so C=5C=5, giving statement (B). Statements (C) and (D) use (x−1)(x-1) and fail.

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