2019 THREE(b)

The graph below shows the function $y=f(x)$.

(i) Find all the value(s) of $x$ which meet each of the following conditions:

1. $f^{\prime }(x)=0$:

2. $f(x)$ is not differentiable:

(ii) What is the value of ${\lim }_{x\to 1}f(x)$?

State clearly if the value does not exist.