- Show that
cosθ=(u⋅v)/(|u||v|)for 2D vectors u and v.
(it is quite hard to come up with these challenges, so if you got any ideas, please post them)
this post was submitted on 25 May 2024
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Daily Maths Challenges
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Share your cool maths problems.
Complete a challenge:
- Post your solution in comments, if it is exactly the same as OP's solution, let us know.
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Making one additional note here, because of your parenthetical message, letting you know that my short backlog of problems I found interesting has actually run dry with the last one I posted - so my series is unfortunately on hiatus. I'll still post if I come across other interesting problems but that honestly doesn't happen too often - even the ones I have posted were collected (and saved by a friend) over several years.