Match the following. Column-I contains functions and Column-II contains number of non-differentiable points in their respective domains  

Column-I		Column-II
A)	$f_1\left(x\right)=||x-6|-|x-8||-|x^2-4|+3x-{|x-7|}^3,x\in R$	P)	2
B)	$f_2\left(x\right)=(x^2-9)|x^2+11x+24|+\sin |x-7|+$$\cos |x-4|+{(x-1)}^{3/5}\sin (x-1),x\in R$	Q)	5
C)	$f_3\left(x\right)=\{\begin{array}{ccc}{(x+1)}^{3/5}-\frac{3\pi }{2}& ,& x<-1\\ (x-\frac{1}{2}){\cos }^{-1}(4x^3-3x)& ,& -1\le x\le 1\\ {(x-1)}^{5/3}& ,& 1<x<2\end{array}$	R)	3
D)	$f_4\left(x\right)=\left\{\sin x\right\}\left\{\cos x\right\}+\left({\sin }^3\pi \left\{x\right\}\right)\left[x\right],x\in [-1,2\pi ]$ (where [.] denotes the greatest integer function and {.} fractional part function)	S)	4

$f_1\left(x\right)=||x-6|-|x-8||-|x^2-4|+3x-{|x-7|}^3,x\in R$ is not differentiable at 

$x=-2,2,6,7\&8$ 
B) $f\left(x\right)=(x^2-9)|x^2+11x+24|+\sin |x-7|+\cos |x-4|+{(x-1)}^{3/5}\sin (x-1)$  is continuous $\forall x\in R$ and not differentiable at  $x=-8\&7$
C)  $f\left(x\right)=\{\begin{array}{cc}{(x+1)}^{3/5}-\frac{3\pi }{2}& :x<-1\\ (x-\frac{1}{2}){\cos }^{-1}(4x^3-3x)& :-1\le x\le 1\\ {(x-1)}^{5/3}& :1<x<2\end{array}$
is continuous not differentiable at  $x=-1,-\frac{1}{2}\&1$
D)  $f\left(x\right)=\left\{\sin x\right\}\left\{\cos x\right\}+\left({\sin }^3\pi \left\{x\right\}\right)\left(\left[x\right]\right),x\in [-1,2\pi ]$
Let  $g\left(x\right)=\underset{cont.atx-1}{\underbrace{\left(\sin \pi \left\{x\right\}\right)\left(\left[x\right]\right)}}\left({\sin }^2\pi \left\{x\right\}\right)$
$g\text{'}\left(I^{+}\right)=g\text{'}\left(I^{-}\right)$  so differentiable at x = 1 and for  $\left\{\sin x\right\}\left\{\cos x\right\}$
Doubtful points for non differentiability are  $x=0,\frac{\pi }{2},\pi ,\frac{3\pi }{2}$
$\because \left\{\sin x\right\}-\left\{\cos x\right\}$  is discontinuous at  $x=0,\frac{\pi }{2},2\pi$
So not differentiable at  $x=2n\pi ,2n\pi +\frac{\pi }{2}$