What is the smallest positive value of N , such that there exists (not necessarily positive) integers x and y satisfying
2 0 1 3 x + 3 1 0 2 y = N ?
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Ok so if N is 33, what are the values of x and y then? I was able to factorise the equation to get ,
33(61x+94y)=N
but how exactly do u prove N=33 ?
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61 and 94 are relatively prime, so there exist x and y such that 64x+91y=1=N/33. Since 1 is the smallest positive number, N=33.
Why do you need to find x , y in the first place as far as the problem is concerned? Also we are asked for the minimum N, so if N is a multiple of 33, then what would be the minimum N? 33 of course, right? Even if you want to find x , y , then 6 1 x + 9 4 y = 1 will have a solution as g c d ( 6 1 , 9 4 ) = 1 can be expressed as a linear combination of 61,94 .
another method
On trying x=6 and y= -4 I get N = 30, which is <33 ??
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Something must have gone wrong, because N is necessarily a multiple of 3 3 .
Wrap your math equations in \ ( \ ) instead of \ [ \ ]. That would fix your 'alignment issue'.
It is not so much d divides ax + by but that:
ax + by = d for some integers x and y
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Please elaborate, I mean why "it is not so much d divides ax+by but that :................" . d is the gcd right?
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There might be a many combinations of numbers that satisfies the equation.
Dear Math Slayer, there may be more than 1 pair of (x,y). Ithink u can get them jst by trail and error or the euclidean algorithm
here is my finding...
2013-> 3 x 11 x 61
3102-> 2 x 3 x 11 x 47
if one has to find x and y then clearly
3 x 11(61x + 94y)
minimize the brackets part multiplied by 33 will be the answer, and it's minimum value can be 1
but wait.. how can you be so sure that you can achieve 1 with the bracket expression. If there is any standard theorem then please let me know. *I need proof *
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Well mate, there always exists a solution to the equation in the bracket, given the condition that the co-efficient of of x,y are co-prime to each other.
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It's called Bezout's Lemma. The process used to get the solution is called the (extended) Euclidean Algorithm.
hey guys just review my solution please...2013 x+3012y=N 2013(x+y)+999 y=N let x=3 and y=-2 2013-1998=N=15 so N=15 right????
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its 3102 y in the question not 3012 as you have stated
well can u make out if any of the x, y that gives N=33
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I mean you want to find the x,y for which the equation holds? Scroll down someone found the values.
Easy method: I used brute-forced method using python, I made an assumptions for both x and y, values ranging from -100 to 100. I created an array ARR as container of the possible values of N, where N=2013 x+2013 y. Then, I used the minimum function "min" and min(ARR)=33. Lastly, I put it on the answer box and gotcha it is the correct answer.
We'll try to see a more general case -
By the Euclidean algorithm, we know that g c d ( a , b ) = a x + b y
We know that g c d ( a , b ) gives us the smallest value of a x + b y for any integers x and y
Hence, in particular the smallest value of N = 2 0 1 3 x + 3 1 0 2 y would definetely be g c d ( 2 0 1 3 , 3 1 0 2 )
Now 2 0 1 3 = 3 × 1 1 × 6 1 and 3 1 0 2 = 2 × 3 × 1 1 × 4 7 , so g c d ( 2 0 1 3 , 3 1 0 2 ) turns out be 3 3
Hence, the smallest value of N = 3 3
Is it always that
g
c
d
(
a
,
b
)
=
a
x
+
b
y
or such that there exist integers x,y such that
g
c
d
(
a
,
b
)
=
a
x
+
b
y
.
So you mean to say
a
x
+
b
y
always gives the gcd?
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N is not 33 but multiple of 33 to get N = 33, (61x + 94y) = 1 I found (61x + 94y) = 5 so N = 165
I mean to say that there exists integers x , y
such that g c d ( a , b ) = a x + b y
Thanks for easy method
least value must be obtained from the difference of 2013x and 3102y. since if x is -1 and y=1, difference will be 1089. To make this value smaller, take it, multiplied by 2 and minus 2013, we have 165. 165 multiplied by 19 or multiplied by 12, take 2013-165 12 or 165 19-3102 to obtain 33...
According to Bezout's Lemma, the minimum positive value that can be written in the given form has to be the GCD of the integers (2013, 3012) . GCD of the numbers is 33 . Therefore the solution is 33 .
By Bezout's lemma the smallest possible positive N is gcd(2013, 3102)=33.
probably the best method like Guinness, probably the best beer
What is Bezout's lemma?
Well, the gcd between 2 0 1 3 and 3 1 0 2 is 3 3 , therefore 3 3 ∣ N , i.e.,
3 3 × k = N > 0 ∴ k = 1 ⇒ N = 3 3
x=38 and y=(-24)
2013x38+3102x(-24)=74484-74481=33
umhhh nice
we know that gcd(a,b) can be written as ax+by for integers x,y hence 2013x+3102y = gcd(2013,3102) which is the least N..
From theorem we get, g c d ( a , b ) = a x + b y for any integer x and y.
In the above problem, 2 0 1 3 x + 3 1 0 2 y = N can be written as, g c d ( 2 0 1 3 , 3 1 0 2 ) = N .
By further simple calculation it can be calculated that g c d ( 2 0 1 3 , 3 1 0 2 ) = 3 3
Therefore The answer is N = 3 3 .
A simple Diophantine Equation, Find gcd of the coeficients and you get the answer !
The greatest common divisor of a and b is the smallest positive linear combination of a and b .
It is a known fact of the Euclidean Algorithm that the smallest positive value of N such that there exists (not necessarily positive) integers x and y satisfying a x + b y = N is gcd ( a , b ) .
Thus, the answer is gcd ( 2 0 1 3 , 3 1 0 2 ) = 3 3 .
gud
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See guys, looking at it you can see that it's a linear Diophantine equation in 2 variables. of the form a x + b y = N . Now suppose g c d ( a , b ) = d ,where a , b , x , y , d are integers .Now for the existence of a solution ,as d divides a x + b y ..........so in turn, d must divide N.
( Well this is because if g c d ( a , b ) = d , then d divides both a and b, so d divides a x + b y for integers x , y )
So, in order for the existence of solution of the given equation, g c d ( 2 0 1 3 , 3 1 0 2 ) = 3 3 must divide N . So 33 must divide N,i.e N must be a multiple of 33. Clearly the smallest such N is 33 . Well this is my first time I wrote a solution and also that using the code, so sorry for the disalignment in writing.