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#26 Help Me ! » What is sine in math » 2023-06-24 00:06:40

Hannibal lecter
Replies: 1

What is sine and cose
Is sine is a length of something or a degree
I can't imagine the sine how thry measure it
Is it illusion quantity
If sine is a ratio then the degree ia a ratio too
So is sine same as degrees
Or there interactive example of a sine

However if the degree is 60 i can find sin and if aegree is 40 I'll get cos by dividing the opposite by adjucent
Also 90 if wanna find tan

What if the degree is 25 or 170 or 35? What will happen

#27 Help Me ! » Degree of angles » 2023-06-23 23:22:56

Hannibal lecter
Replies: 1

I always stuck in degree of angel
I don't know the meaning of 90 or 45 or 30

Is it a the length of traingle?
I am cery simple in measure i know how to measure
Area or distance using a roller
But what is 90 is it a quantity of two sides of a triangle
Sometimes i can see in my bare eyes the length of something easily
But when i see degree i get confused
Also what is sine of a degree

#28 Help Me ! » Archimedes and limit 2 » 2023-06-23 22:58:47

Hannibal lecter
Replies: 1

I have main question about limit
Why archimesdes used two polygon
One inscribed in a circle and second circumscribed around the circle
Why he didn't use only one polygon
Can u interpret this gor me in very easy way pleaee
Because i think it enough to use yhe inscribed polygon to measure the perimeter of the circle

Also archimesdes used " Archimedes used a basic geometry including properties of circle and polygon
ratios of sides of triangles to calculate polygon perimeter (would not have used the word "sine" in his work, as this term was not used until much later in history)"

May i know what is these
1) basics geometry
2) properties of circle abd polygon
3) ratios of sides of traingle
Specially the ratios!! What r these
Is there a book ir websites to illustrate these all of them where can i study these and learn about
Please it's my last question about archimesdes i need fullfill illustratetion in details without using sine and cos and modern calculation method
I want to find Pi just like him and at my home

#29 Re: Help Me ! » from napier book » 2023-06-23 22:11:21

this is the book shared bia google drive

https://drive.google.com/file/d/1eYeHtD4H-hnJdYAVTAxtSB_DY4zkhpS7/view?usp=sharing


I don't know if you can download it I found it on web
it's a translated version for the original book of john napier

#30 Help Me ! » Archimedes and limit » 2023-06-23 04:42:59

Hannibal lecter
Replies: 1

Archimedes of Syracuse first developed the idea of limits to measure curved figures and the volume of a sphere in the third century b.c. By carving these figures into small pieces that can be approximated, then increasing the number of pieces, the limit of the sum of pieces can give the desired quantity

how was Archimedes  doing that? is there examplew with simple numbers for a simple sphere or any curved figure

what what does " the limit of the sum " mean?

#31 Re: Help Me ! » from napier book » 2023-06-23 04:17:39

also allow me to quote this :-

Arithmetical progressions : 1, 2, 3, 4, 5, 6, 7,
&c. ; or 2, 4, 6, 8, 10, 12, 14, 16,
Geometrical progressions: 1, 2, 4, 8, 16, 32, 64,
or 243,81, 27, 9, 3, 1.
in these progressions we require accuracy and ease in
working. Accuracy is obtained by taking large numbers
for a basis ; but large numbers are most easily made from
small by adding cyphers,

Thus instead of 100000, which the less experienced make the greatest sine, the more learned
put 10.000.000, whereby the difference of all sines
is better expressed. Wherefore also we use the
same for radius and for the greatest of our geometrical proportional.

what does he put? he just increase the zeros it's mean he changed the number is that accuracy?

#32 Help Me ! » from napier book » 2023-06-23 04:09:49

Hannibal lecter
Replies: 14

Besides this, there is another rule for accuracy ; that is to say, when an unknown or incommensurable quantity is included between numerical limits not differing by many
units.
Thus if the diameter of a circle contain 497
parts, since it is not possible to ascertain precisely
of how many parts the circumference consists, the
more experienced, in accordance with the views of
Archimedes, have enclosed it within limits, namely
1562 and 1561. Again, if the side of a square
contain 1000 parts, the diagonal will be the square
root of the number 2000000. Since this is an in- commensurable number, we seek for its limits by
extraction of the square root, namely 1415 the
greater limit and 1414 the less limit, or more
accurately 1414(604/2828) greater, and 1414 (604/2829)

I searched a lot but I didn't find these what is 1562 greater limit and 1561 less limit
also what is 1414(604/2828) greater, and 1414 (604/2829)

if the side of square contain 1000 parts the diagonal will be the square root of number 2000?
isn't that should be 1 * square root of 2
why he put six zeros?
that book is talking about accuracy right now
also what is these numbers the 1414? and the 1561

#33 Re: Help Me ! » How to make a schedule for four employ 3 shifts each one has 8 hourday » 2023-06-23 03:23:53

Bob wrote:

if I have 3 employee only

But, from what you have said, that won't happen. You are planning to have lots more and that makes it easy to avoid unfilled duties.

If you've got 50 employees, call that 49 plus one spare. The spare fills in to cover absences.

The 49 can be 7D + 7D + 7D + 7A + 7A + 7A + 7N and, by distributing them like I have said you have every duty covered as the days off are staggered.

Perhaps you should start from the other end and ask 'How many staff do I want on duty at each time to ensure good coverage?"  Round those numbers up to a multiple of 7 and you can set up the rotas.  With that number you should have a few spares to fill in for absences.

Bob


They are supervisors the 4 employee
But at checkpoint fir example I need 21 employee at A shift and at D shift and at N shift less
At terminal I need 25 every A,D and N shift

Thier sum is 46 lets say 50 per shift
So how many extra employees I need to cover the OFF days  Don't know if they are enough or not
I want to know the specific number
To get less cost so no need to employee a lot of employees for nothing
For example if i got 50 and need 6 more
That's less cost from employee 17 extra one for nothing

#34 Help Me ! » Continuous progressions, » 2023-06-23 01:52:36

Hannibal lecter
Replies: 1

continuous progressions, an arithmetical is one which proceeds by equal intervals

a geometrical, one which advances by unequal and proportionally increasing or
decreasing intervals.


I didn't understand the meaning of that can you please illustrate this in plain English and by numbers or examples?


From web i found : Arithmetic progression is a sequence of numbers where the difference between any two consecutive numbers is the same. For example, series 1,2,3,4 is an arithmetic progression that has a common difference
The difference is 1

I know that but at the top it said, "is one which proceeds by equal intervals."

What is mean these sentence? I don't know what it means by saying proceeds by equal intervals.
From the example above I don't see any intervals I searched a lot I didn't see any arithmetic continuous progressions with intervels only a series and a common difference must of the websites
And does he mean by "proceeds" he mean increasing?
And is arithmetic continuous progressions is the same as Arithmetic sequence? Which I found in https://www.mathsisfun.com/algebra/sequences-sums-arithmetic.html

#35 Re: Help Me ! » How to make a schedule for four employ 3 shifts each one has 8 hourday » 2023-06-22 05:56:47

I have a late question then I'll continue to work on this pattern you provided to me
but first may I know something
if I have 3 employee only I can't make a schedule lick that
because for example :
Sat    Sun     Mon     Tue     Wed      Thu       Fri
A       A       A        A      A      A      X     -------x1
D       D       D       D      D      X     D     -------x2
N       N       N       X      N      N     N     -------x3


mr bob every time the one of these employee goes off we miss someone at a specific time
for example look at Tuesday the X3 got off in that day so no one exist at NightShift(10PM-6AM) note that the 10PM started in monday and that shift ended 6AM in Tuesday we called it the nightshift

so obviously we need 1 extra employee to solve that problem

my question is what if we have 50 employees do I need 10 extra employees to solve the situation?
how to calculate how many extra employee I need in general

#36 Re: Help Me ! » How to make a schedule for four employ 3 shifts each one has 8 hourday » 2023-06-21 08:00:12

Now my question is if x4 isa flip employee to cover the off days
How much flip employees i need if tger is 50 employee or 200

Because you know if i have x1 and x2 and x3 i can't maje this schedule without x4 because there will be days without anyone at or 0 zero days
But what about large numberes
How many i need

#37 Re: Help Me ! » How to make a schedule for four employ 3 shifts each one has 8 hourday » 2023-06-18 08:25:04

Why there is DDAD and AAAD
I want everyweek to still same like six days and sixs nights continuously how to do that

Also your schedule has a small mistake there is eight A it has to be 6 A then OFF
And is there general equation for that

Also the employees are security officers in airport
I Can't just do it with 28 days
They have to work the whole month I don't want the airport be empty from the officers every morning i need and officer at list and everynight and afternoon the other 225 are security inspectors also i need at least 70 of them at daylight and 70 at afternoon and 60 of them at night
No problem with night can be lesser because night is not important there is less passengers traveling at night

#38 Re: Help Me ! » How to make a schedule for four employ 3 shifts each one has 8 hourday » 2023-06-18 04:48:52

Also my last problem with that os how to apply
That schedule for 200 employee or 250

#39 Re: Help Me ! » How to make a schedule for four employ 3 shifts each one has 8 hourday » 2023-06-18 04:06:27

the second problem I got as you will see in the next photo..

the first photo I show to you was in month May
in the second photo it's the next month which is June schedule


2023-06-18-185938.png



in the May the day1 start at Monday until  Day5 which is Friday which is the OFF day of X1 employee
so I started to fill and trying and tests thier schedules according to this
but at Day31 of May it was Wed and it was (D) shift for the X1 employee the end of the month
then at June the sixth Month it most continue in (D) shift until his Friday OFF
so I can't save the pattern inside my mind and apply it for each month because it has to be a specific calculations for each months
because some month also start for example at Sunday which is the OFF of the X3 employee
I just want to make a schedule  so I make sure I don't make any mistakes
and I want to know how to customize it for example I want to change few things like I want in Day5 2 employee at afternoon shifts instead of them at Daylight shift

#40 Re: Help Me ! » How to make a schedule for four employ 3 shifts each one has 8 hourday » 2023-06-18 02:02:29

A mean afternoon(2PM to 10PM)
D mean Daylight (6AM-2PM)
N mean night (from 10PM to 6AM)

There is four employees lets say instead of these names in yellow the : x1 x2 x3 and x4

Yes no problem if an employee got same day work
Like x1 abd x2 went at work togather in afternoon
But I prefer must of that occur at day and afternoon usually
Because we don't need a lot of employee at night one is enough

Also each employee has one day off per week not mater the day monday or Friday or any random day
And no problem if two employees or more has the same day off but onl61 day per week only

This happen every 1 month (31 days) sometimes 30 days or 29
but the day off is constant for the whole year or for ever

Is there equation for this how to calculate

#41 Help Me ! » How to make a schedule for four employ 3 shifts each one has 8 hourday » 2023-06-17 07:39:16

Hannibal lecter
Replies: 11

It has 3 math night from 10pm to 6AM and day from 6AM to 2pm and afternoon from 2pm to 10PM each one 8 hours then each one has 1 day off per week or per 6 days so how to do it using your sequare please send me the chart as photo
For example
for example for this month please she the pic

2023-06-18-003305.png

the schedule is wrong I was trying to do it manually it still wrong

How to handle this

#42 Re: Help Me ! » Different angles in term of points of view » 2023-06-09 03:04:16

Bob wrote:

hi Hannibal lecter

Is this a question about calculating angles and 'views' in 3D ?  I wish you hadn't used a gun to illustrate your post.  This is Maths Is Fun. Not much fun in a device that is used for killing people!  Perhaps you could modify your post to make it more fun.

how many views it will have 20 25 or what

What do you mean here?  A 360 degree rotation means there's an infinite number of angles of view.  If you could be more specific about the issue I may be able to help with some 3D geometry. In the past I have helped posters using vector geometry and also trigonometry in 3D.  But I need more information.

The guns view are from x-ray screen machine
How many views the bag will have on the screen

Bob


Yes in 3D I need main views only like that gun look how many views are there for it, what if it's a bag of a woman or a shoe for example any object

#43 Help Me ! » Different angles in term of points of view » 2023-06-08 05:33:01

Hannibal lecter
Replies: 3

How to calculate Different angles in term of points of view
Like this gun in the photo below it has 35 views in the display
Lets say a stabdard  bag of a woman .
how many views it will have 20 25 or what


Screenshot-20230608-202739-Drive-2.jpg

#44 Help Me ! » Hello » 2023-03-15 20:46:46

Hannibal lecter
Replies: 2

I have this lock:
a 3 dials combination I want to open it I forger the password
simplexpick0x.gif


I want the full number list to try them all please they said it's 1000 numbers

#45 Re: Help Me ! » compare between numbers using Boolean expressions » 2022-10-03 23:50:48

EPSILON = 1E-14;
r = sqrt(2.0)

if  abs(r * r - 2.0) < EPSILON
output :-
sqrt(2.0) squared is approximately 2.0

this when I use java but when I use Microsoft calculator it said false! the condition would be false not true as you can see in this picture :-

2022-10-04-144854.png


also as you can see in this example :-

double x = 9.999999999999999;
if (Math.abs(x- 10.0) < EPSILON)
{
System.out.println("the number is approximately 10"); 
    }
}
}

when I minus the 9.999999999999999 to 9.99 for example the condition will be false!




in short I just want to solve this question :-

Explain why it is more difficult to compare floating-point numbers than integers.
Write Java code to test whether an integer n equals 10 and whether a floating-point
number x is approximately equal to 10

#46 Help Me ! » compare between numbers using Boolean expressions » 2022-09-12 04:43:20

Hannibal lecter
Replies: 3

Hi,

if (-0.01 < x - y && x - y < 0.01)
         {
            print : "The numbers are close together");
         }

what is the meaning of -0.01?
and how could we compared between two numbers distance using this short unknown expression?
I mean for example I'll try two close numbers but it didn't work like :
x = 1, y= 0.5
like :
(-0.01 < 1 - 0.5 && 1 - 0.5 < 0.01)
( true && false )
the result is false !!!! so the numbers are not close but they are close it's 1 and 0.5 look 0--0.5--1.5--2-2.5...

so the numbers are not close togather? is that expression wrong? and if it's wrong what is the correct one

#47 Help Me ! » translate math words into » 2022-03-17 03:10:36

Hannibal lecter
Replies: 1

hi, I saw this in a book can someone translate these highlighted words into numbers because I get confused in English some times

1

1.jpg

2

2.jpg


3


3.jpg

#48 Re: Help Me ! » dividing small number over a larger number concept » 2022-03-17 03:05:56

Bob wrote:

Let's say you want to do 1 / 3 as a decimal.

Let's try 100 / 3 first.

100 - 3 = 97         97 - 3 = 94         Oh dear! This will take ages.  Let's speed it up by taking 30 at a time.

100 - 30 = 70      70 - 30 = 40         40 - 30 = 10

Now I haven't got enough left to take another 30 so I'll switch to taking 3s.

10 - 3 = 7       7 - 3 = 4      4 - 3 = 1 

Now I haven't got enough to take any more 3s so I'll switch to taking away 0.3 each time.

1 - 0.3 = 0.7        0.7 - 0.3 = 0.4        0.4 - 0.3 = 0.1   

This is going to go on forever because I always get a bit left over. 
If I was setting this out as a division the answer space would have this:

33.333333

If I want to do 1 / 3, it's exactly the same except the decimal point shifts two places left.

1 / 3 = 0.33333333

Bob


I understand everything now completely but that last segment of your post it's a little not clear to me
because you take 100 - 3 until you reached 40 - 30 = 10 then stopped (first time)
then you take 10 - 3 = 7       until you reached      4 - 3 = 1  then stopped (second time)
finally you take 1 - 0.3 = 0.7        until you reached        0.4 - 0.3 = 0.1  then stopped (third time)
so the number would be 0.3? right? it's 3 times right?? how it's 33.333333 or 0.33333333 it should be 0.3 right

#49 Re: Help Me ! » dividing small number over a larger number concept » 2022-03-16 13:20:48

So we record that in the answer space as not 4 subtracts but 0.4 subtracts because we shifted the carriage one place.

I mean we made 15 become 1.5 the number is changed who gives the right to do such a thing is that legal in math and clearly understandable? is there explaintion for that ..
I mean we chose a different number it's 1.5
I can't imagine that is there interactive example like 6 apples iver 16 people

#50 Re: Help Me ! » dividing small number over a larger number concept » 2022-03-16 07:47:23

First you try 6 - 15.  Cannot do that as you're trying to take away too much.  So 'shift the carriage' and try to take away 1.5s.  You can do that exactly 4 times; 6 - 1.5 - 1.5 - 1.5 - 1.5 = 0.  So we record that in the answer space as not 4 subtracts but 0.4 subtracts because we shifted the carriage one place.

bob why we can't do repeated subtraction
like 8 ÷ 4
8 - 4 = 4 (1 time)
4 - 4 = 0 (1 time)
then the result is 2

why in 5 ÷ 16 you said (Cannot do that as you're trying to take away too much)
what you mean by that can you please explain further to me


and after that you said :-

, so 'shift the carriage' and do 1 - 0.6 = 0.4.  You can do that once but then there's not enough left to do it again.

what you mean by "there is not enough left"

can you please explain that further for a beginner

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