`int(x^2+1)/(x^2-2x+2)^2dx`
Let's evaluate the above integral by rewriting the integrand as,
`int(x^2-2x+2+2x-1)/(x^2-2x+2)^2dx`
`=int(x^2-2x+2)/(x^2-2x+2)^2dx+int(2x-1)/(x^2-2x+2)^2dx`
`=int1/(x^2-2x+2)dx+int(2x-1)/(x^2-2x+2)^2dx`
Now again rewrite the second integral,
`=int1/(x^2-2x+2)dx+int((2x-2)+1)/(x^2-2x+2)^2dx`
`=int1/(x^2-2x+2)dx+int(2x-2)/(x^2-2x+2)^2dx+int1/(x^2-2x+2)^2dx`
Now let's evaluate the above three integrals,
`int1/(x^2-2x+2)dx=int1/((x-1)^2+1)dx`
Let's use the integral substitution,
Let u=x-1,
du=dx
`=int1/(1+u^2)du`
The above can be evaluated using the standard integral,
`int1/(x^2+a^2)dx=1/atan^(-1)(x/a)`
`=1/1tan^(-1)(u/1)`
`=tan^(-1)(u)`
Substitute back u=x-1,
`=tan^(-1)(x-1)`
Now let's evaluate the second integral by integral substitution,
`int(2x-2)/(x^2-2x+2)^2dx`
Let `v=(x^2-2x+2)`
`dv=(2x-2)dx`
`=int1/v^2dv`
`=v^(-2+1)/(-2+1)`
`=v^(-1)/-1`
`=-1/v`
Substitute back `v=(x^2-2x+2)`
`=-1/(x^2-2x+2)`
Noe let's evaluate the third integral,
`int1/(x^2-2x+2)^2dx`
`=int1/((x-1)^2+1)^2dx`
Let's use the integral substitution,
Let `tan(y)=x-1`
`sec^2(y)dy=dx`
`=int(sec^2(y)dy)/(tan^2(y)+1)^2`
Using the identity:`1+tan^2(y)=sec^2(y)`
`=int(sec^2(y))/(sec^2(y))^2dy`
`=int1/(sec^2(y))dy`
`=intcos^2(y)dy`
Now use the identity:`cos^2(y)=(1+cos(2y))/2`
`=int(1+cos(2y))/2dy`
`=int(1dy)/2+intcos(2y)/2dy`
` ` `=y/2+1/2sin(2y)/2`
`=y/2+sin(2y)/4`
Substitute back `y=tan^(-1)(x-1)`
`=1/2arctan(x-1)+1/4sin(2arctan(x-1))`
`=1/2arctan(x-1)+1/4{2sin(arctan(x-1))cos(arctan(x-1))}`
`=1/2arctan(x-1)+1/4{2*(x-1)/sqrt(x^2-2x+2)*1/sqrt(x^2-2x+2)}`
`=1/2arctan(x-1)+(1/2)(x-1)/(x^2-2x+2)`
`:.int(x^2+1)/(x^2-2x+2)^2dx=arctan(x-1)-1/(x^2-2x+2)+1/2arctan(x-1)+(x-1)/(2(x^2-2x+2))`
Add a constant C to the solution and simplify,
`=3/2arctan(x-1)+(-2+x-1)/(2(x^2-2x+2))+C`
`=3/2arctan(x-1)+(x-3)/(2(x^2-2x+2))+C`
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