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#1 2014-11-09 02:25:37

SolarDevil
Member
Registered: 2014-09-14
Posts: 37

Lattice Point Question

What is the answer to this question?

A lattice point is a point whose coordinates are both integers. How many lattice points are on the boundary or inside the region bounded by

and
?

Once I get the answer I can review the solution.

SolarDevil


Herro! Sycamore School will win National Science Bowl this year!!! big_smile

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#2 2014-11-09 02:49:54

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Lattice Point Question

Hi;

Looks like an infinite number.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#3 2014-11-09 03:02:22

SolarDevil
Member
Registered: 2014-09-14
Posts: 37

Re: Lattice Point Question

Well, it is bounded so no. When I graph it, it forms a weird figure. I think they mean by bound as the surrounding stuff around the enclosed region.

Thanks,
SolarDevil


Herro! Sycamore School will win National Science Bowl this year!!! big_smile

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#4 2014-11-09 03:10:15

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Lattice Point Question

Bounded meaning what here?


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#5 2014-11-09 03:12:13

SolarDevil
Member
Registered: 2014-09-14
Posts: 37

Re: Lattice Point Question

Surrounding the figure that is formed by the intersection of the two graphs


Herro! Sycamore School will win National Science Bowl this year!!! big_smile

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#6 2014-11-09 03:13:21

ShivamS
Member
Registered: 2011-02-07
Posts: 3,648

Re: Lattice Point Question

bobbym wrote:

Bounded meaning what here?

I'm assuming he means that there is some real number P such that |f(x)|≤P for all x in the domain of definition of f. So it can't be infinite.

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#7 2014-11-09 03:15:05

SolarDevil
Member
Registered: 2014-09-14
Posts: 37

Re: Lattice Point Question

ShivamS wrote:
bobbym wrote:

Bounded meaning what here?

I'm assuming he means that there is some real number P such that |f(x)|≤P for all x in the domain of definition of f. So it can't be infinite.


Yup.


Herro! Sycamore School will win National Science Bowl this year!!! big_smile

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#8 2014-11-09 03:19:42

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Lattice Point Question

Have you checked the graph what area are we looking at?


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#9 2014-11-09 03:20:14

SolarDevil
Member
Registered: 2014-09-14
Posts: 37

Re: Lattice Point Question

Yes we are looking at the area on top that is surrounded by the two graphs. It as an oval end on the top and a pointy end on the bottom (the pointy end is on (0,0))

Last edited by SolarDevil (2014-11-09 03:21:25)


Herro! Sycamore School will win National Science Bowl this year!!! big_smile

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#10 2014-11-09 03:30:13

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Lattice Point Question

I get 28 in that region just by counting them.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#11 2014-11-09 03:30:39

SolarDevil
Member
Registered: 2014-09-14
Posts: 37

Re: Lattice Point Question

Okay. Thanks!


Herro! Sycamore School will win National Science Bowl this year!!! big_smile

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#12 2014-11-09 03:31:27

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Lattice Point Question

Hold on, you should check my work at least!


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#13 2014-11-09 03:31:41

SolarDevil
Member
Registered: 2014-09-14
Posts: 37

Re: Lattice Point Question

Hmm... the answer was 29. What did we miss. I get 28 as well after counting. Maybe the origin?

EDIT: oh, I did miss the origin.

Thanks!
SolarDevil

Last edited by SolarDevil (2014-11-09 03:32:33)


Herro! Sycamore School will win National Science Bowl this year!!! big_smile

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#14 2014-11-09 03:32:26

ShivamS
Member
Registered: 2011-02-07
Posts: 3,648

Re: Lattice Point Question

Try using the Shoelace Theorem and then Pick's theorem.

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#15 2014-11-09 03:33:21

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Lattice Point Question

Yes, he can use that for for a shape.

We both missed the origin.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#16 2014-11-09 03:34:37

ShivamS
Member
Registered: 2011-02-07
Posts: 3,648

Re: Lattice Point Question

bobbym wrote:

Yes, he can use that for for a shape.

Yeah, I didn't graph this before. sad

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#17 2014-11-09 03:35:54

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Lattice Point Question

That is okay, I can not even count passed 25 correctly.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#18 2014-11-09 03:39:21

SolarDevil
Member
Registered: 2014-09-14
Posts: 37

Re: Lattice Point Question

What does a question mean if a variable is inversely proportional to another variable?

Ex: You are given that x is directly proportional to

, and y is inversely proportional to
.  If the value of x is 3 when z is 12, what is the value of x when z is equal to 75?  Express your answer as a common fraction.

Last edited by SolarDevil (2014-11-09 03:40:26)


Herro! Sycamore School will win National Science Bowl this year!!! big_smile

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#19 2014-11-09 03:39:30

ElainaVW
Member
Registered: 2013-04-29
Posts: 580

Re: Lattice Point Question

You broke your favorite rule:

Never do anything by hand! Let the computer do it!

I will tell Eric, will he be amused.

Last edited by ElainaVW (2014-11-09 03:39:45)

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#20 2014-11-09 03:42:26

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Lattice Point Question

Yes, I broke his favorite rule. I learned nothing.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#21 2014-11-09 03:50:36

SolarDevil
Member
Registered: 2014-09-14
Posts: 37

Re: Lattice Point Question

SolarDevil wrote:

What does a question mean if a variable is inversely proportional to another variable?

Ex: You are given that x is directly proportional to

, and y is inversely proportional to
.  If the value of x is 3 when z is 12, what is the value of x when z is equal to 75?  Express your answer as a common fraction.


Could someone help?


Herro! Sycamore School will win National Science Bowl this year!!! big_smile

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#22 2014-11-09 07:13:01

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Lattice Point Question

If x is directly proportion to y^3 you can say x = k * y^3, where k is the constant of proportionality.

If y is inversely proportional to √z then y = k / √ z.

http://www.mathsisfun.com/algebra/direc … ional.html


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

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