Question

which of the following graph is a function

Answer 1

The first curve is the only function out of the 4 choices

Answer 2

You can check if a graph is a function or not using the vertical line test.

Answer 3

If any vertical line x = k, where k is an element of the set of the domain of the graph, cuts the graph at more than 2 points, then the graph is not a function.

Answer 4

The first one only is a function and the rest are relations. That is because when you cut the graphs, only graph 1 is cut once, and the others when cut, touch more than one place of the graph.

Answer 5

Oops, I meant cut the graph more than one time.

Answer 6

I also meant vertically, like TURITW said.

Answer 7

and when graph 1 is cut only 1 point of the graph is touched.