∫(1->e^2)dx/(x√(1+lnx))
=∫(1->e^2)dlnx/√(1+lnx)
=∫(1->e^2)d(lnx+1)/√(lnx+1)
=2√(lnx+1)|(1->e^2)
=2[√(lne^2+1)-√(ln1+1)]
=2[√(2+1)-√1]
=2√3-2