Question

The range of $f(x)=[\cos x]$, where $[x]$ is the greatest integer less than or equal to $x$, is

• A. (-1,1)
• B. \{-1,0\}
• C. \{1,0\}
• D. \{-1,0,1\}
• E. [-1,1]

Hint:

Logic Tip: Brackets like $\{\}$ denote a set of discrete values, whereas parentheses $()$ and square brackets $[]$ denote continuous intervals. Since the greatest integer function strictly outputs integers, the answer must be a discrete set, eliminating options A and E immediately.

Answer 1

The Correct Option is D