The denominator of any fraction cannot be equal to zero. This is because if the denominator is equal to zero, the, the fraction itself would be "undefined".
Applying this to the above mentioned problem, we will find two denominators including the term "x". These two denominators cannot be equal to zero.
First fraction:
1/x ..................> x cannot be equal to zero
Second fraction:
1/(x^2 - 3x -4) = 1/(x - 4)(x + 1)
The denomination will be equal to zero if x = 4 or x = -1
........> x cannot be equal to 4 or -1
Based on this, the restrictions on x are as follows:
x cannot be equal to 0,4 or -1