If [cos−1x]+[cot−1x]=0 , where [.] denotes the greatest integer function, then complete set of values of  x  is

0≤cos−1x≤π  ⇒ [cos−1x]=0,1,2, or 3 0≤cos−1x≤π  ⇒ [cot−1x]=0,1,2, or 3 ⇒ [cos−1x]+[cot−1x]=0 ⇒ [cos−1x]=0,  [cot−1x]=0 ⇒ 0≤cos−1x<1, 0cos1 , set of values of x  is (cot1,1] .