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M1 vectors

I can never work out how to calculate parallel vectors, e.g.Given that c=3i+4j and d=i-2j find t if d-tc is parallel to -2i+3jI've tried using algebra but then I come out with two unknowns which I can't find. Please help!
Original post by wheelerc
I can never work out how to calculate parallel vectors, e.g.Given that c=3i+4j and d=i-2j find t if d-tc is parallel to -2i+3jI've tried using algebra but then I come out with two unknowns which I can't find. Please help!


dtc=(13t)i(2+4t)j then just equate that to k(2i+3j) d-tc=(1-3t)i-(2+4t)j \text{ then just equate that to }k(-2i+3j) and solve for k.
(edited 9 years ago)

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