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vectors help

https://imgur.com/a/MHqTSX0
not really understanding much of the question tbh. ive been trying to figure out if theres a shortcut using further maths knowledge with the dot product but i cant really think of anything, thanks
Original post by Gent2324
https://imgur.com/a/MHqTSX0
not really understanding much of the question tbh. ive been trying to figure out if theres a shortcut using further maths knowledge with the dot product but i cant really think of anything, thanks


You can just draw a diagram.

Start with some origin of your choice. now draw on the vectors m and n coming out of it, in whatever directions you want them to. Now draw on where the vector m-n is going.

Carry on from there, by joining the tips of the vectors for m and (m-n) , realising that this line is parallel to the vector n.
Original post by RDKGames
You can just draw a diagram.

Start with some origin of your choice. now draw on the vectors m and n coming out of it, in whatever directions you want them to. Now draw on where the vector m-n is going.

Carry on from there, by joining the tips of the vectors for m and (m-n) , realising that this line is parallel to the vector n.


im not seeing where its parallel

i got a triangle now, find out the other angle using (sin30)/6 = (sinx)/3, x = 14.47, 180-30-14.47 = 135.5 , does that sound correct?
Original post by Gent2324
im not seeing where its parallel

i got a triangle now, find out the other angle using (sin30)/6 = (sinx)/3, x = 14.47, 180-30-14.47 = 135.5 , does that sound correct?


Going from tip of m to tip of (m-n) is the same as starting on tip of m and going along the vector -n to reach tip of (m-n)... and this journey vector of -n is obviously parallel to n.

Your answer looks good.

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