You can view the animation that shows the [color=#0a971e][i]sum [/i][/color]and [color=#b20ea8][i]difference[/i][/color] of the vectors displayed using the parallelogram method, simply clicking the related buttons.[br]To show just the vectors, click the [color=#888][i]Restart[/i][/color] button.[br][br]At the end of the animation, move the [color=#6aa84f]green points[/color] that define the vectors positions to explore how their sum and difference modify accordingly.[br]Which reciprocal position do they need to take in order to make the [color=#1551b5]parallelogram method not applicable[/color]?[br]In this particular case, [color=#c51414]how can you do to calculate the sum and difference of the two vectors[/color]?