Old Ironsides
✝️ Christmaxxing subhuman nigger
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@IronsideCel
@IronsideCel
We should start posting israel vs Palestine here so we can make this thread more relevantmfw the last few posts in the math thread haven't been math
Then I guess I'll take it upon myself to save the math thread from such base brutality.We should start posting israel vs Palestine here so we can make this thread more relevant
Feels like I am reading this wrong. Because the condition seems to be false. Just substitute 25 for a, 125 for b and 32 for cLet a,b,c be rational numbers. Prove that a*sqrt(2) + b*sqrt(3) + c*sqrt(5) is rational if and only if a = b = c = 0.
No, that would only work if it was sqrt(a) + root(b,3) + root(c,5) was the task.Feels like I am reading this wrong. Because the condition seems to be false. Just substitute 25 for a, 125 for b and 32 for c
Well, then I have no idea what he's talking aboutNo, that would only work if it was sqrt(a) + root(b,3) + root(c,5) was the task.
Yep. To use the language of linear algebra, it's indeed well-known that {1, sqrt(2)} is linearly independent over the rational numbers. I'm essentially positing that {1, sqrt(2), sqrt(3), sqrt(5)} (even with sqrt(7) adjoined in the bonus) is linearly independent over the rationals as well.You might have learned the proof that sqrt(2) is not rational. I guess this is essentially a generalization of that
can you say that sinceLet a,b,c be rational numbers. Prove that a*sqrt(2) + b*sqrt(3) + c*sqrt(5) is rational if and only if a = b = c = 0.
Bonus (much harder): Let a,b,c,d be rational numbers. Prove that a*sqrt(2) + b*sqrt(3) + c*sqrt(5) + d*sqrt(7) is rational if and only if a = b = c = d = 0.
is rational iff a = b = 0, ik i have to prove the smaller iff statements separately but not bothered to write it out rna*sqrt(2) + b*sqrt(3)
is rational iff b = c = 0b*sqrt(3) + c*sqrt(5)
is also rational iffa*sqrt(2) + 2b*sqrt(3) + c*sqrt(5) + (-b*sqrt(3)) (-do this proof separate)
and finding 0 is rationala*sqrt(2) + b*sqrt(3) + c*sqrt(5)
Unfortunately, I don't think so. The problem I see is with the following step:is this a legit way to do it?
In general, the sum of two irrational numbers can be rational (e.g., add π to 4 - π). I wouldn't know how the prove the aforementioned step (from the smaller cases). If you have an idea, however, I'd love to hear it.then the sum -
is also rational iffa*sqrt(2) + 2b*sqrt(3) + c*sqrt(5) + (-b*sqrt(3)) (-do this proof separate)
a = b = c = 0
This reminds me of when i used to send my homework into facebook groups in highschool and the people on there did if for free and for no reasonPost all math related problems and solutions here. Don't cheat.
First problem: If the coefficients of x³ and x^4 in the expansion of (1+ ax+ bx² ) (1−2x) ^18 in powers of x are both zero, then (a, b) is equal to?
They just wanted to brag about knowing the subjectThis reminds me of when i used to send my homework into facebook groups in highschool and the people on there did if for free and for no reason
i wish that worked with uni assignments :,)They just wanted to brag about knowing the subject
These problems make me feel retarded
If we have a set of cases where it claims the foid enjoyed getting raped, it would be an uncountable set.
In ZF every set admits a topology.Prove that a topology on the set where foids claimed they didn't enjoy getting raped doesn't exist?
The smallest case is where a + b in Q implies at least a or b is in P. The trivial case, of course, is where a or b is 0. For all a + b in P where a or b > 0 and a or b in Q, a or b must be zero or the additive inverse.Unfortunately, I don't think so. The problem I see is with the following step:
In general, the sum of two irrational numbers can be rational (e.g., add π to 4 - π). I wouldn't know how the prove the aforementioned step (from the smaller cases). If you have an idea, however, I'd love to hear it.
Quod Erat Demonstrandum? More like Qat Erat Demonstrandum.The smallest case is where a + b in Q implies at least a or b is in P. The trivial case, of course, is where a or b is 0. For all a + b in P where a or b > 0 and a or b in Q, a or b must be zero or the additive inverse.
Something something, proof by contradiction or exercise left for the reader. □
Quod Erat Demonstrandum? More like Qat Erat Demonstrandum.
Averagw IQ traitMan this thread reminded me of how fucking much I hate functions
@Grim_Reaper @CountBleckLet A be an n by n matrix satisfying A^3 = 0. Prove that rank(A^2) ≤ n/2.
What's your level?PLEASE, post a math problem that is simple enough for me to solve to feel smart BUT not too hard that I can't solve it.
I'm not sure, slightly higher than an average normie who barely knows math.What's your level?
High school level math then? How about this problem:I'm not sure, slightly higher than an average normie who barely knows math.
Since A^3 = 0, then im(A^2) is a subset of ker(A^2) which is a subset of ker(A). Let k be the dimension of im(A^2) and let n-k be the dimension of ker(A^2). Then dim(im(A^2)) ≤ dim(ker(A^2)) so k ≤ n - k which implies k ≤ n/2 so rank(A^2) ≤ n/2@Grim_Reaper @CountBleck
The only way for this to be true is if A^2 = 0, which is not necessarily the case. Consider for example a 3 by 3 Jordan block with 0 along the diagonal.im(A^2) is a subset of ker(A^2)
Would it be safe to assume that rank(A^2) ≤ rank(A), so rank (A^2) + rank(A) ≤ rank(A^2*A) + n -> rank(A^2) + rank(A) ≤ n so rank(A^2) ≤ n/2?The only way for this to be true is if A^2 = 0, which is not necessarily the case. Consider for example a 3 by 3 Jordan block with 0 along the diagonal.
Yes, that'd be correct. The rank of a matrix is the dimension of its image, so the obvious im(A^2) ⊆ im(A) implies that rank(A^2) ≤ rank(A). Nicely done.Would it be safe to assume that rank(A^2) ≤ rank(A), so rank (A^2) + rank(A) ≤ rank(A^2*A) + n -> rank(A^2) + rank(A) ≤ n so rank(A^2) ≤ n/2?
If linear algebra was a girl, I'd so fuck her.Fucking linear algebra.
If lin alg was a girl, I'd hate fuck her. I loved the abstract algebra and group theory that came later, but lin alg can go to hell.If linear algebra was a girl, I'd so fuck her.
If you like group theory but hate linear algebra, how do you feel about representation theory?If lin alg was a girl, I'd hate fuck her. I loved the abstract algebra and group theory that came later, but lin alg can go to hell.
I haven't looked into it. It's covered in graduate algebra courses that I didn't take.If you like group theory but hate linear algebra, how do you feel about representation theory?
Linear algebra would be a bratty teen slut while group theory would be a roastie.If lin alg was a girl, I'd hate fuck her. I loved the abstract algebra and group theory that came later, but lin alg can go to hell.
Group theory would be the porn milf with the body of a 25 year old. Accurate representation (KEK) of lin alg, tbh.Linear algebra would be a bratty teen slut while group theory would be a roastie.