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[billclintonsdad]

what the FUCK is a dot-product? If anyone can help IN ANY WAY, PLEASE RESPOND.

Comments

[rabid_lilac]

okay i did a math project on this

you use the dot product to find the angle between two vectors

i forget exactly how to find the dot product itself but there are many websites that have the formula, just google it

basically if you have two vectors, you use the magnitudes of those vectors to find the dot product and then once you have the dot product you can find all this other cool shit

[billclintonsdad]

ok thanks

[dghettoazngurl]

wtf

[chrisbah]

oh claire is so wise in the ways of math and libraries

[insaneinside]

dot product a · b, where a and b are vectors:
a · b = axbx + ayby [+ azbz]

So: (5, 4) · (2, 8) = (5)(2) + (4)(8) = 10 + 32 = 42
(Hey! It really is the answer to life, the universe and everything!)

Angle between two vectors, a and b, remembering that |a| is the length of a:
θ = cos-1((a · b)/(|a||b|))

(which is derived, by the way, from the formula "a · b = |a||b|cosθ")

[billclintonsdad]

thank you SOOO much. you are my hero. That's the only thing I've seen that actually makes sense.