Hi team,

in the video Dimensionality Reduction and Projection

I don’t get it why two vector multiply together will get the direction on the same line?

Like in the picture, [1.2, 1.6] * [1,1] will get the point on the same direction as [1,1]

*" To choose that orange vector note that the line y equals x is actually*

*the span of the vector with coordinates 1, 1.*

*So let’s use that vector 1, 1.*

*Now if you take the dot product of that first row in the table and the orange*

*vector, you’re essentially saying take 1 times the point x coordinate and*

*one time the point y coordinate to find the new location projected along the line."*

I understand that two vector’s dot product is equal to **l2-norm u * l2-norm v * cosin**, if norm are on the same direction then cosin = 1, but I can’t relate this to two different direction vector… as the angle is not 0, so where is the cosin?