kill(all)$

van=facebook.com/LearningCalculus$

assume(lower > 0, a > 0, a > lower);

F:integrate(1/x,x,lower,a)=((6*%i-w)/(6*w^2+%i))^2 - w;

a:rhs(first(solve(F,a)))$

logcontract(subst(2*%i*w^32/sqrt(6+2*w+6*w^2),lower,a));