Pure maths, physics, logic (braingames.ru): non-trade-related brain games - page 157

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_RAVen:

When starting at noon, the maximum speed between the hands is at 403 seconds and repeated after 3927 seconds (calculation is accurate to a second). Distance 27 mm

I don't know how you arrived at this, but the answer is correct. There is, by the way, a very simple solution based on kinematics, using the tangent and secant theorem. The same answer can be obtained by the cosine theorem, etc., but it will be a kilo of writing (which is exactly what we see in Mathemat, although I must give him credit, his answer is also correct, it means that his calculations are correct and the method itself is also correct, though rather tense and complicated).

In kinematics, a description of motion is introduced, schedules are made of where what body will be with what speeds and accelerations. The question of where velocities and accelerations come from does not come up in kinematics - it is left for dynamics.
Kinematics has in fact been dealt with by all astronomers for thousands of years. Copernicus moved to the reference system associated with the Sun and not the Earth and found, as Alexey did in the problem about the arrows, that in this system the picture of the movement of the planets is many times simpler.

 

There are 2012 black dots and one white dot on a circle. Among the set of all polygons with vertices at these points, which will be more with or without white dots?

Weight 1, because the problem is new. I think it will be higher with time.

 
it's as simple as that
 
Mischek:
it seems so simple.
What's the answer?
 
I assume the same amount. I haven't figured out my logic yet, but I think I've come to that conclusion.
 
Mathemat:
What's the answer?
without
 
An acquaintance of mine solved it just the other day, yesterday/the day before. Apparently it really isn't difficult. got it right on the first try :)
 
Road_king:
An acquaintance of mine solved it just the other day, yesterday/the day before. It seems to be really easy. they got it right on the first try :)
and what was the answer?
 
Mischek:
and which answer counts?

I got a "c".

The modders who made the decisions have doubts as to whether the wrong answer counts. But the answer does seem to be correct.

 
Mathemat:
I got a "c".
is passed as correct ?
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