question_answer

If \[\text{cosec}\theta -\cot \theta =a,\] then the value of \[\cot \theta \] is:

A)  \[\frac{a-1}{2a}\]                     

B)  \[\frac{1-{{a}^{2}}}{2a}\]

C)  \[{{a}^{2}}-1\]                      

D)  \[\frac{{{a}^{2}}-1}{{{a}^{2}}+1}\]

E)  None of these