Respuesta :

Answer:

[tex]log x-\frac{log(x^{2}+1) }{2}-tan^{-1} x[/tex]

Step-by-step explanation:

step 1:-   by using partial fractions

[tex][tex]\frac{1-x}{x(x^{2}+1) } =\frac{A(x^{2}+1)+(Bx+C)(x }{x(x^{2}+1) }[/tex]......(1)

step 2:-

solving on both sides

[tex]1-x=A(x^{2} +1)+(Bx+C)x......(2)[/tex]

substitute x =0 value in equation (2)

1=A(1)+0

A=1

comparing x^2 co-efficient on both sides (in equation 2)

0 = A+B

0 = 1+B

B=-1

comparing x co-efficient on both sides (in equation 2)

-1  =  C

step 3:-

substitute A,B,C values in equation (1)

now  

[tex]\\\int\limits^ {} \, \frac{1-x}{x(x^{2}+1) } d x

=\int\limits^ {} \frac{1}{x} d x +\int\limits^ {} \frac{-x}{x^{2}+1 }  d x -\int\limits \frac{1}{x^{2}+1 }  d x[/tex]

by using integration formulas

i)  by using [tex]\int\limits \frac{1}{x}   d x =log x+c........(a)

\\\int\limits \frac{f^{1}(x) }{f(x)} d x= log(f(x)+c\\[/tex].....(b)

[tex]\int\limits tan^{-1}x  dx =\frac{1}{1+x^{2} } +C[/tex].....(c)

step 4:-

by using above integration formulas (a,b,and c)

we get answer is

[tex]log x-\frac{log(x^{2}+1) }{2}-tan^{-1} x[/tex]