[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

View post   
File: 32 KB, 387x505, DogSuit.jpg [View same] [iqdb] [saucenao] [google]
4515856 No.4515856 [Reply] [Original]

Ok /sci/ would anyone help me with that?
I got to translate this into a plan.

Just a single problem : I don't even know how to read it, let alone translate it.

So here is the formula:
B= [ (x,y) e R² / x² + y² =< 1]

First I want to know how to read that.
Is it correct if I assume it means :

Function B is equal to ( variables x, y ) that are rational numbers ² excluding x² + y ² that can be equal or inferior to 1 ?


then again I got others like this one:
A u B =[ (x,y) e R² / (x,y) e A, v (x,y) e B]

But let's just stay on the first one.
Is it correct? and then how do I draw it on a plan once I have the x and y values?

>> No.4515881

B= [ (x,y) e R² / x² + y² =< 1]
reads as:
B is the set of x and y from R^2 such that x^2 + y^2 is less than or equal to 1.

B contains all x and y within and on the border of a circle in the x,y-plane with radius 1.

>> No.4515888

>>4515881
continuing:
A u B =[ (x,y) e R² / (x,y) e A, v (x,y) e B]
reads as:
the cross section of sets A and B are all x and y from R^2 such that x and y are in A OR x and y are in B.

>> No.4515889

>>4515881
How do you see it's a circle?

>> No.4515892

>>4515888
oh man you're being very kind, thank you so much.
I'm recording that to remember it.
I gotta go sleep now tomorrow I'll try to understand it more.


What I don't get is where do you read circle and where do you read radius?

>> No.4515895

>>4515889
x^2 + y^2 = c is the equation for a circle, so you have a continuous set of circles with c ranging from 0 to 1, non formally put: this yields a circular plane with radius 1 in which all x and y from B lie.

>> No.4515902

>>4515895
I see!
So it's a circle with a center B = 0 and radius x or y = 1 cm?

diameter = 2?

thanks I get it now.
I didnt know x² + y² was equation/values for a circle.

>> No.4515906

>>4515892
as I stated in >>4515895, x^2 + y^2 = c is the equation for a circle. When x = 0, y must equal either c or -c. When y = 0, x must be equal to c or -c. The rest of the circle is Pythagoras' Theorem applied, basically: c is the unchanging hypotenuse and with x you have a fixed y.

>> No.4515911

>>4515902
wait for a bit, I'll make you a drawing

>> No.4515923

>>4515906
so either the line that goes from y or x to x or y is c?

>> No.4515925

>>4515911
hum, ok

>> No.4515929
File: 1.90 MB, 3264x2448, photo.jpg [View same] [iqdb] [saucenao] [google]
4515929

I hope this clears things up a bit!

>> No.4515936

>>4515929
it does.
thanks a lot.
If only /sci/ was full of people like you instead of elitist pricks.

>> No.4515941

>>4515936
The elitism is in many cases a cover for not having to answer questions they're themselves are not really sure of how to solve ;)

Glad to help, good luck!

>> No.4515952

By the way, I messed up a little in an earlier post! In >>4515888 I said "cross section", but this should have read "unification" instead!

>> No.4515968

>>4515952
what's the difference between unification (U) and crosss section (⋂)?

>> No.4515976

>>4515968
The unification of two sets A and B contains all elements of A and B, the cross section of two sets A and B contains only the elements that both are in A and B.

>> No.4516000

>>4515976
thx