1) y' = (x*ln(x^2+1)+ln5)'=ln(x^2+1)+x(ln(x^2+1))'= ln(x^2+1)+(2x^2)/(x^2+1)
2) y'=(sin(x/2)*cos(3x/2))'=1/2cos(x/2)*cos(3x/2)-3/2sin(x/2)sin(3x/2)
