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  1. Alright, future engineers!
    **Logarithm:** The exponent a base needs to be raised to, to get a specific number.
    Ex: `log_2(8)=3` means `2^3=8`.
    Pro-Tip: Think what power? Logs *undo* exponentials. Master this link!
    #AlgebraBasics #MathHelp #STEM #StudyNotes

  2. OK I'm going to need ask the Fediverse for some math help here, because I have a feeling I'm forgetting something obvious and can't find the resources I'd need to answer my own question.

    Let's say I have an underdetermined linear system. The methods generally employed to solve these find the least (l2) norm solution, which is generally acceptable.

    However, in my case, I need to find solutions that satisfy some constraint (simple inequality constraints: solution must be in a box, with known ranges [min max] for each variable).

    I think I have had a brain freeze because the only approach I can think of to solve this is to turn the problem into a constrained optimization problem. However, in my case (hundreds of thousands of variables) this is not computationally feasible: the time needed for the optimization approach is ridiculously higher than the standard linear system solution.

    OTOH, I have a vague feeling that it should be possible to approach this differently, possibly remaining in the domain of the linear system resolution. What am I missing?

    #askFedi #fediHelp #askMath #mathHelp #mathematics

  3. I have a fun math coincidence on my family: every year the birthday for both my parents and I is on the same weekday. All of them is past February, so this is always true.

    What's the probability of this happening?
    Is it as simple as P(x) = 1/7*1/7*1/7 or do we take anything in consideration to properly calculate the probability? #math #mathhelp #fedihelp #probability #hivemind

  4. Today I'm having a really slow #math brain day. I'm trying to reduce an expression so that I can write it in terms of derivatives and possibly simplify the proof that it has a given Taylor series expansion.

    I've currently managed to write the original expression in terms of a certain function f(x) and its first two derivatives as:

    f(x) f''(x)/(f'(x)^2)

    or equivalently

    ( f(x) / f'(x) ) / ( f'(x)/f''(x) )

    which I've managed to express as

    D( log(f'(x)) / D( log(f(x)) )

    (D being the derivative operator) but this seems like a dead end. I feel like there's something trivial escaping me. #mathHelp

  5. #math #lexicon question (sorry, I studied these things in Italian, so I don't know the English term). How do you call a sequence or series whose terms have alternating signs *but only after a few terms*?

    Think something like
    1 1 1 1 1 1 1 1 -1 1 -1 1 -1 ...

    #mathHelp

  6. Yes, I'm still doing "Free Tutoring Tuesdays on Twitch"! Join me for some #GGST and/or #mathhelp from 3:30-6pm/7:30-10 EST. twitch.tv/suburbanlion

  7. Trying to implement Euler's equations for fluid dynamics, but my values keep NaNing out...
    I suspect I missunderstand the gradient of tensor product of u time rho*u...

    Can't get it to make sense in my head...

    #eulersequation #physics #mathhelp