344. Find the derivative of the function $y=\arcsin \ln x$.
Solution. We again apply the formula $(\arcsin u)^{\prime}=\frac{u^{\prime}}{\sqrt{1-u^{2}}}$ :

$$
y^{\prime}=(\arcsin \ln x)^{\prime}=\frac{(\ln x)^{\prime}}{\sqrt{1-(\ln x)^{2}}}=\frac{1}{x \sqrt{1-\ln ^{2} x}} .
$$