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elements of statistics
kropki game

The dot product of vectors "a" and "b" we can calculate from magnitude of vectors |a|, |b| and angle α between them. a ⋅ b = |a| |b| cosα. The dot product of vectors "a" and "b" we can calculate too from their coordinates [a_1,a_2] and [b_1,b_2]. a ⋅ b = [a_1,a_2] ⋅ [b_1,b_2] = a_1b_1 + a_2b_2. If dot product of vectors equals 0 then these vectors are perpendicular. (cos90° = 0). Examples. Magnitude of vectors. Coordinates of vectors. The dot product of vectors equals 0 then these vectors are perpendicular.