∫ln(x+1)/√(x+1)dx
=∫ln(x+1)/√(x+1)d(x+1)
=2∫ln(x+1)d√(x+1)
=2√(x+1) ln(x+1)-2∫√(x+1) * 1/(x+1) dx
=2√(x+1) ln(x+1)-2∫ dx/√(x+1)
=2√(x+1) ln(x+1)-4√(x+1) +C