We have, \displaystyle f(x)={\begin{matrix}{\int }_{0}^{x}(5+|1-t|)dt, & x>2 \\ 5x+1, & x\leq 2\end{matrix}
Therefore, f(x)=∫01(5+(1−t))dt+∫1x(5+(t−1))dt
=6−21+(4t+2t2)∣1x
=211+4x+2x2−4−21
=2x2+4x+1
Now, f(2+)=2+8+1=11
and f(2)=f(2−)=5×2+1=11
Here, f(2+)=f(2−)
So, f(x) is continuous at x=2
Clearly, f(x) is differentiable at x=1
Now, LHDf′(2−)=5 and RHDf′(2+)=6
Therefore, f(x) is not differentiable at x=2