Linear combination
Instructions
First, move the two blue points whose default locations are  and . These points determine the vectors  and . Notice as you do this the light blue lines move. The intersections of blue lines show terminal points of the linear combination  for integer values of  and .
The vector  is depicted in black, and you can change the values of  and  using the purple sliders. A purple parallelogram shows the geometric depiction of adding the vector  and the vector .