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    104 points nomemory | 18 comments | | HN request time: 2.75s | source | bottom
    1. sevensor ◴[] No.42186490[source]

        sin x = x
    
    Half the problems in EE become trivial once you learn this. Sometimes the universe does a bad job of complying with the approximation though.
    replies(4): >>42186803 #>>42186842 #>>42187116 #>>42187823 #
    2. pkoird ◴[] No.42186803[source]
    I am not sure I understand. Sin(x) approaches x only when x approaches 0. When else does the universe does a bad job with this approximation?
    replies(2): >>42186824 #>>42187076 #
    3. philipov ◴[] No.42186824[source]
    sin(x)=x in the same way that c=π=1 when doing cosmology.
    replies(1): >>42186875 #
    4. dotancohen ◴[] No.42186842[source]
    Are you familiar with the Taylor series? That's the first organ of the Taylor series, something like two decades ago I checked how accurate it goes past 20 organs:

    https://dotancohen.com/eng/taylor-sine.php

    replies(2): >>42188006 #>>42190301 #
    5. bubblyworld ◴[] No.42186875{3}[source]
    At least you can often recover the constants after the fact with dimensional analysis in cosmology =P
    replies(1): >>42186932 #
    6. mr_mitm ◴[] No.42186932{4}[source]
    1=c=G=hbar and sometimes =k is not even a joke, that's just natural units. Pi=e=1 however ... is only half a joke, because cosmologists are often only interested in orders of magnitudes, and even those are sometimes approximated.
    7. adgjlsfhk1 ◴[] No.42187076[source]
    the joke is that sometimes the universe is bad at making sure x always approaches 0.
    8. m463 ◴[] No.42187116[source]
    pi = 3.2

    (that is an assignment statement)

    https://en.wikipedia.org/wiki/Indiana_pi_bill

    replies(1): >>42188960 #
    9. setopt ◴[] No.42187823[source]
    Since e^(2πi) = 1, we can also conclude that e^(2πifx) = 1^(fx). This makes Complex Fourier Transforms quite trivial.
    10. sevensor ◴[] No.42188006[source]
    Oh yeah, for sure. And if you like a good time, compare the Taylor series at x=0 for sin(x) to that for exp(jx).
    11. wmwmwm ◴[] No.42188960[source]
    My aero engineering friend from university winds me up every time I see him saying that pi = 22/7 - I finally stopped getting angry, checked and it’s pretty good! I’m still glad he didn’t decide to design planes after he graduated though!
    replies(2): >>42188996 #>>42190101 #
    12. defrost ◴[] No.42188996{3}[source]
    That was a near miss for the industry, real aerospace nerds use 355/113 ...
    13. nomemory ◴[] No.42190101{3}[source]
    Fun fact, in the book Life Of Pi, the kid stays exactly 227 days on the boat with the tiger.
    14. xelxebar ◴[] No.42190301[source]
    > That's the first organ of the Taylor series

    Guessing that "organ" is a typo for "order", but somehow I kind of like envisioning Taylor series as living organisms, with terms being individual organelles.

    Thanks for the smile in the morning.

    replies(2): >>42190683 #>>42198121 #
    15. seanhunter ◴[] No.42190683{3}[source]
    No Taylor liked to communicate the series musically on various organs. IT got expensive and that’s why noone ever goes beyond the first two or three terms.
    replies(2): >>42193766 #>>42194118 #
    16. brookst ◴[] No.42193766{4}[source]
    Any sources to Bach that up?
    17. selimthegrim ◴[] No.42194118{4}[source]
    I wonder what Grassmann did
    18. xg15 ◴[] No.42198121{3}[source]
    Was thinking of organ pipes and imagining it as the first tune. Might also be fitting.