Let f : R →R be a function defined by f(x) = [x]2 + [x + 1] – 3 {where [.] denontes greatest integer function}, then f(x) is
(A) many-one
(B) onto
(C) one-one
(D) into
Correct Option:- (A) (D)
Explanation :-
f(x) = [x]2 + [x] – 2
Let [x] = t
f(t) = t2 + t – 2 = (t + 2) (t – 1)
so f(x) is may - one into