Integral Calculus Question 25

Question: Correct evaluation of $ \int_{{}}^{{}}{\frac{x}{(x-2)(x-1)}\ dx} $ is

[MP PET 1993]

Options:

A) $ {\log_{e}}|\frac{{{(x-2)}^{2}}}{(x-1)}|+p $

B) $ {\log_{e}}|\frac{(x-1)}{(x-2)}|+p $

C) $ \frac{x-1}{x-2}+p $

D) $ 2{\log_{e}}|( \frac{x-2}{x-1} )|+p $ (where p is an arbitrary constant)

Show Answer

Answer:

Correct Answer: A

Solution:

$ \int_{{}}^{{}}{\frac{x}{(x-2)(x-1)},dx}=-\int_{{}}^{{}}{\frac{1}{x-1},dx+\int_{{}}^{{}}{\frac{2}{x-2},dx}} $ $ =-|{\log_{e}}(x-1)+2{\log_{e}}(x-2)|+c={\log_{e}}\frac{{{(x-2)}^{2}}}{(x-1)}+p. $