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riddle
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Ok, so I'm new to vectors, and I've been reading up on them and I think I understand how parallel vectors work, or at least instinctively.
a || xa, where x is a constant.
So I started doing some questions from my textbook, and I could manage, but I'm not sure if what I'm doing is the most efficient way to solve the problems.
For example:
Find s if 3i+4j -s(i-2j) is parallel to 2i + j
What I've done is:
3i+4j -s(i-2j)
=> 3i+4j -si + 2js = x(2i+j)
=> i(3-s) + j(4+2s) = 2xi+jx
=> 3-s = 2x, and
4+2s = x
=> 3-s = 2(4+2s)
=> 3-s = 8 + 4s
=> 3-8 = 4s + s
=> -5 = 5s
=> s = -1
When it comes to math I've never believed in there being a "correct" way to do stuff, but in this case, is there a "better" way to do these sorts of problems?
a || xa, where x is a constant.
So I started doing some questions from my textbook, and I could manage, but I'm not sure if what I'm doing is the most efficient way to solve the problems.
For example:
Find s if 3i+4j -s(i-2j) is parallel to 2i + j
What I've done is:
3i+4j -s(i-2j)
=> 3i+4j -si + 2js = x(2i+j)
=> i(3-s) + j(4+2s) = 2xi+jx
=> 3-s = 2x, and
4+2s = x
=> 3-s = 2(4+2s)
=> 3-s = 8 + 4s
=> 3-8 = 4s + s
=> -5 = 5s
=> s = -1
When it comes to math I've never believed in there being a "correct" way to do stuff, but in this case, is there a "better" way to do these sorts of problems?
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