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The dot product a·b = axbx + ayby + azbz measures projection and gives the angle through cos θ = a·b/(|a||b|). The cross product is perpendicular to both, and its magnitude equals the area of the parallelogram they span.
Dot product
a · b = axbx + ayby + azbz = |a||b|cos θ
Cross product
a × b = (aybz − azby, azbx − axbz, axby − aybx)
a·b = 4 − 10 + 18 = 12, and a × b = (27, 6, −13).
The vectors are parallel or antiparallel, so they span no area.