Rajdeep
Last Activity: 6 Years ago
Hello there!
According to me, there is no such rule to identify when to use what (scalar product or vector product).
You need to understand the question and the approach to solve the question.
If in the question, it is stated that the vectors A and B are perpendicular,
use
dot product = 0, as dot product of
, and cos 90 = 0.
If in the question, it is stated that the vectors A and B are parallel,
use cross product = 0, as cross product of
, and sin 0 = 0.
If two vectors A and B represent the two adjacent sides of a parallelogram,
then the area of the parallelogram is the cross product (or vector product) of the two vectors.
If two vectors A and B represent the two sides of a triangle,
then the area of the triangle is half the cross product of the two vectors.
