how to use fromPointToLatLng on google maps v3 .

Question

This is my code:

var latlng = new google.maps.LatLng(-34.397, 150.644);
var myOptions = {
          zoom: 8,
          center: latlng,
          mapTypeId: google.maps.MapTypeId.ROADMAP
        };
        map = new google.maps.Map(document.getElementById("map_canvas"),
            myOptions);
        google.maps.event.addListener(map,'projection_changed', function () {
            ltBound=map.getProjection().fromPointToLatLng(new google.maps.Point(0,100))
            rbBound=map.getProjection().fromPointToLatLng(new google.maps.Point(100,200))
            console.log(ltBound,rbBound)
        });

I want to make a node on google maps, but i can't use the fromPointToLatLng on right way. What can i do?