`intx/(x^2-6x+10)^2dx`
Let's rewrite the integrand as,
`=1/2int(2x)/(x^2-6x+10)^2dx`
`=1/2int(2x-6+6)/(x^2-6x+10)^2dx`
`=1/2[int(2x-6)/(x^2-6x+10)^2dx+int6/(x^2-6x+10)^2dx]` --------------------(1)
Now let' evaluate each of the above two integrals separately,
`int(2x-6)/(x^2-6x+10)^2dx`
Let's apply integral substitution:`u=x^2-6x+10`
`=>du=(2x-6)dx`
`=int1/u^2du`
`=intu^(-2)du`
Now from the integer tables:`intu^ndu=u^(n+1)/(n+1)+C`
`=u^(-2+1)/(-2+1)`
`=-1/u`
Substitute back `u=x^2-6x+10`
`=-1/(x^2-6x+10)` -----------------------------(2)
Now let's evaluate the second integral,
`int6/(x^2-6x+10)^2dx`
Take the constant out,
`=6int1/(x^2-6x+10)^2dx`
Complete the square of the term in the denominator.
`=6int1/((x-3)^2+1)^2dx`
Let's apply integral substitution:`u=x-3`
...
`intx/(x^2-6x+10)^2dx`
Let's rewrite the integrand as,
`=1/2int(2x)/(x^2-6x+10)^2dx`
`=1/2int(2x-6+6)/(x^2-6x+10)^2dx`
`=1/2[int(2x-6)/(x^2-6x+10)^2dx+int6/(x^2-6x+10)^2dx]` --------------------(1)
Now let' evaluate each of the above two integrals separately,
`int(2x-6)/(x^2-6x+10)^2dx`
Let's apply integral substitution:`u=x^2-6x+10`
`=>du=(2x-6)dx`
`=int1/u^2du`
`=intu^(-2)du`
Now from the integer tables:`intu^ndu=u^(n+1)/(n+1)+C`
`=u^(-2+1)/(-2+1)`
`=-1/u`
Substitute back `u=x^2-6x+10`
`=-1/(x^2-6x+10)` -----------------------------(2)
Now let's evaluate the second integral,
`int6/(x^2-6x+10)^2dx`
Take the constant out,
`=6int1/(x^2-6x+10)^2dx`
Complete the square of the term in the denominator.
`=6int1/((x-3)^2+1)^2dx`
Let's apply integral substitution:`u=x-3`
`=>du=dx`
`=6int1/(u^2+1^2)^2du`
Now use the following from the integration tables:
`int1/(a^2+-u^2)^ndu=1/(2a^2(n-1))[u/(a^2+-u^2)^(n-1)+(2n-3)int1/(a^2+-u^2)^(n-1)du]`
`=6{1/(2(1)^2(2-1))[u/(1^2+u^2)^(2-1)+(2(2)-3)int1/(1^2+u^2)^(2-1)du]}`
`=6{1/2[u/(1+u^2)+int1/(1^2+u^2)du]}`
Now from the integration table:`int1/(a^2+u^2)du=1/aarctan(u/a)+C`
`=6{1/2[u/(1+u^2)+arctan(u/1)]}`
`=(3u)/(1+u^2)+3arctan(u)`
Substitute back `u=x-3`
`=(3(x-3))/(1+(x-3)^2)+3arctan(x-3)`
`=(3x-9)/(1+x^2-6x+9)+3arctan(x-3)`
`=(3x-9)/(x^2-6x+10)+3arctan(x-3)` -------------------------(3)
Plug back the results of the integrals 2 and 3 in 1
`int1/(x^2-6x+10)^2dx=1/2[-1/(x^2-6x+10)+(3x-9)/(x^2-6x+10)+3arctan(x-3)]`
`=1/2[(3x-9-1)/(x^2-6x+10)+3arctan(x-3)]`
`=1/2[(3x-10)/(x^2-6x+10)+3arctan(x-3)]`
`=(3x-10)/(2(x^2-6x+10))+3/2arctan(x-3)`
Add a constant C to the solution,
`=(3x-10)/(2(x^2-6x+10))+3/2arctan(x-3)+C`
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