Sal determines the domain of a function that models going up and down a ladder.
Domain of modeling functions is a free educational video by Khan Academy.It helps students in grades 9,10,11,12 practice the following standards HSF.IF.B.5.
1. HSF.IF.B.5 : Relate the domain of a function to its graph and, where applicable, to the quantitative relationship it describes. For example, if the function h(n) gives the number of person-hours it takes to assemble n engines in a factory, then the positive integers would be an appropriate domain for the function.