Trigonometry I'll never use that.

[srw]

I don't do numbers if I can help it (a bit dyscalculic), but isn't this (trigonometry) what most people do unconsciously when planning their trajectory for crossing a road? We recognise the speed of approaching vehicles and adjust the angle/length of crossing route accordingly. I probably haven't explained that very well, but it intrigues me that most of the time we do this effortlessly.

A senior economist at the Bank of England noticed that dogs are able to catch Frisbees without being able to spot, let along understand or explain, that when they do that they are solving simultaneous partial differential equations in what passes for their doggy brain.

He presented a paper on the subject at a very obscure banking regulation conference in the Southern US and thereby caused a major storm among those who risk-manage and regulate financial services firms across the world.

 

[MartinQ]

There was quite a good explanation of how people catch balls in how to dunk a donughnut (page 108, amongst other things)
http://www.arvindguptatoys.com/arvindgupta/dunk-doughnut.pdf
by keeping the vertical angle increasing at a constant rate.

 

[jefmcg]

There was quite a good explanation of how people catch balls in how to dunk a donughnut (page 108, amongst other things)
http://www.arvindguptatoys.com/arvindgupta/dunk-doughnut.pdf
by keeping the vertical angle increasing at a constant rate.

Yes, but we are cyclists. Cycling is a sport** for people who have zero hand/eye coordination (and can't swim, so rowing is out).

**yes, cycling is also a form of transport, a leisure activity and a way of life.

 

[marinyork]

It also has* quaternions, and infinities of infinities, and Lie algebras and Galois groups. So why do people only ever get angsty about straightforward complex numbers?

*Platonic mathematical philosophy alert - other brands are available.

welcome back from the land of grumpiness.

It does indeed and I've talked about all of those on these forums and their predecessors.

Complex numbers was what someone was talking about so answered. Binary operations and associativity were covered also by others although we didn't specifically mention lie algebras. If I'd been bad tempered I might have though. Often people do think quaternions are useful. I was trying to find another diagram I liked but then I deleted the one I found and didn't find one to my liking.

 

[midlife]

Pigeons can guide missiles too....

Shaun

 

[subaqua]

It's only i if you're doing maths. For engineering it's j, as I and i are used for current.

Lower case i is not used for current . That is always upper case .

 

[midlife]

Shaun

 

[TheDoctor]

Lower case i is used for instantaneous values of current, such as in resonant circuits.
Damn - too slow!

 

[srw]

welcome back from the land of grumpiness..

Bugger. I thought I'd kept the grumpiness index high.

Just noticed the numerological significance of your member number: 333. It's the number of the beo.

 

[subaqua]

Lower case i is used for instantaneous values of current, such as in resonant circuits.
Damn - too slow!

Deck forgot about that. Shoot am I getting to that point in life.

Good call