.
原式=∫dx/{(x-1)√[(x-1)(x-2)]}=∫dx/[(x-1)√(x^2-3x+9/4-1/4)]=2∫dx/{(x-1)√[(2x-3)^2-1]}
令2x-3=1/cost(,则x=1/(2cost)+3/2
原式=∫sint/cos^2(t)/[(1/(2cost)+1/2)tant]dt=∫2/(cost+1)dt=∫1/cos^2(t/2)dt=2tan(t/2)+C
画个图稍微算一下就知道tan(t/2)=2√[(x-2)/(x-4),所以原式=2√[(x-2)/(x-4)+C