Ceiling Function/Examples/Ceiling of Minus One Half

Theorem

 * $\ceiling {-\dfrac 1 2} = 0$

where $\ceiling x$ denotes the ceiling of $x$.

Proof
We have:
 * $0 \ge -\dfrac 1 2$

and:
 * $-1 = -\dfrac 2 2 < -\dfrac 1 2$

Hence $0$ is the ceiling of $-\dfrac 1 2$ by definition.