In part of a derivation they have, Integrate dx/(1-x) = (1-aW)^(1/2) dW I get -ln(1-x) = (-2/3a)*(1-aW)^(3/2) but they say it's ln(1/(1-X)) = (2/3a)((1-(1-AW)^(3/2)) Can anyone tell me how they get that extra "1-"?