Have i integrated this correctly?

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\int(x-5)/(x2-2x+2)dx

(x-5)/(x2-2x+2)=(x-1-4)/((x-1)2+1)

x-1=t therefore x=t+1

dx=x'dt=(t+1)'dt=dt


\int(x-5)/(x2-2x+2)dx=\int(t-4)/(t2+1)dt

=\intt/(t2+1)dt-4\int1/(t2+1)dt

=0.5ln|t2+1|-4arctg(t)+c
 
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If you differentiate your answer, you should be able to get back to your original integrand.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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