The function 
If
is differentiable at
, then it should be continuous at
.
is a polynomial function in the two intervals, therefore it is continuous at all points in the given intervals .
Check for differentiability at
:
Find the left hand and right hand limits of
at
.
Left hand limit:
.
Right hand limit:

Since left and right hand limits are not equal , So
is discontinuous at
.
Therefore,
is not differentiable at
.
Find the derivative of the function.
Find
when
:

Find
when
:

The derivative of the function
.
Graph of the function
:

Graph of the function
:
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The given function is not differentiable at
.
Graph of the function
is

Graph of the function
is
.