Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section A

Chapter

Indefinite Integration

Question:

The value of the integral $∫e^x(\log\, x+\frac{1}{x})dx$ is:

Options:

$e^xlog\, x+C$, Where C is a constant.

$e^{-x}log\, x+C$, Where C is a constant.

$\frac{e^x}{x}+C,$ Where C is a constant.

$\frac{e^{-x}}{x}+C,$ Where C is a constant.

Correct Answer:

$e^xlog\, x+C$, Where C is a constant.

Explanation:

The correct answer is Option (1) → $e^x\log\, x+C$, Where C is a constant.

$∫\left(log\, x+\frac{1}{x}\right)^{e^x}dx$

$=e^x\log x+C$ as $f(x)=\log x$

$f'(x)=\frac{1}{x}$

so $\int e^x(f(x)+f'(x))dx$

$=e^xf(x)+C$