The function is .

Graph :

Graph of the function : 

(a)

Find .

Observe the above graph.

As  tends to  from left side,  approaches to .

So . 

(b)

Find . 

Observe the above graph.

As tends to from right side, approaches to . 

So . 

(c)

Find . 

Left hand limit . 

Right hand limit . 

Left hand limit and right hand limit are not equal.

does not exist. 

(a) . 

(b) . 

(c) does not exist.