For a non-zero integer a, which of the following is not defined?
Explanation for correct option:
Option A: is a fraction with denominator . The value obtained by dividing any number either positive or negative by is not defined.
Hence, option A is correct
Explanation for incorrect options:
Option B: ; which is a defined value
Option C ; which is a defined value
Option D ; which is a defined value
Hence, options B, C and D are incorrect
Hence, the correct option is option A