1.y'=cosx+sinx(y'|x=π/6)=(3^0.5+1)/22.dy/dx=(1/(lnx^0.5))(1/(x^0.5))(x^(-0.5)/2)dy=(1/(2xlnx^0.5))dx3.f(x^2)=lnxf(x)=lnx^0.5f'(x)=(1/x^0.5)x^(-0.5)/2=1/(2x)