Find all points of discontinuity of f, where f is defined by`f(x)={{:((|x|)/x , ifx!=0),( 0, ifx=0):}`

Explanation

It is known that,

x<0=>|x|=-x and x>0=>|x|=x

The given function `f` is defined at all the points of the real line.

Let `c` be a point on the real line.

Case 1:

If `c<0`, then `f(c)=-1`

`lim_(x->c)f(x)=lim_(x->c)(-1)=-1`

`lim_(x->c)f(x)=f(c)`

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