Definition of the Ceiling FunctionThe ceiling function ceiling(x) is defined as the function that outputs the smallest integer greater than or equal to x. Below is shown the graph of ceiling(x)The domain of ceiling(x) is the set of all real numbers. The range of ceiling(x) is the set of all integers. ExampleEvaluate ceiling(x) for various values of x.ceiling(1.5) = 2 ceiling(0) = 0 ceiling(2) = 2 ceiling( 3) =  3 ceiling( 1.5) =  1
More References and LinksOnline Floor and Ceiling Functions Calculator.Applications, Graphs, Domain and Range of Functions
