By introducing a substitution,
t = 3 ( x − 1 ) 2 − 1 2 ; x = t + 1 2 3 + 1 ; d x = d t 6 2 t + 1 ; ∫ d x 3 x 2 − 6 x + 2 = 1 6 ∗ 2 ∫ d t t + 1 2 t − 1 2 = 1 12 ∫ d t t 2 − 1 4 = 1 12 log ∣ t + t 2 − 1 4 ∣ = 1 2 3 log ∣ 3 ( x − 1 ) 2 − 1 2 + ( x − 1 ) 3 ( 3 x 2 − 6 x + 2 ) ∣ . t = 3(x-1)^2 - \frac{1}{2}; \\
x = \sqrt{\frac{t+\frac{1}{2}}{3}}+1; \\
dx = \frac{dt}{\sqrt{6}\sqrt{2t+1}}; \\
\smallint{\frac{dx}{\sqrt{3x^2-6x+2}}} = \frac{1}{\sqrt{6*2}}\smallint{\frac{dt}{\sqrt{t+\frac{1}{2}}\sqrt{t-\frac{1}{2}}}} = \frac{1}{\sqrt{12}}\smallint{\frac{dt}{\sqrt{t^2-\frac{1}{4}}}} = \frac{1}{\sqrt{12}}\log{|t+\sqrt{t^2-\frac{1}{4}}|} = \frac{1}{2\sqrt{3}}\log{|3(x-1)^2 - \frac{1}{2}+(x-1)\sqrt{3(3x^2-6x+2)}|}. t = 3 ( x − 1 ) 2 − 2 1 ; x = 3 t + 2 1 + 1 ; d x = 6 2 t + 1 d t ; ∫ 3 x 2 − 6 x + 2 d x = 6 ∗ 2 1 ∫ t + 2 1 t − 2 1 d t = 12 1 ∫ t 2 − 4 1 d t = 12 1 log ∣ t + t 2 − 4 1 ∣ = 2 3 1 log ∣3 ( x − 1 ) 2 − 2 1 + ( x − 1 ) 3 ( 3 x 2 − 6 x + 2 ) ∣ .
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