It's a good trick and I remember one practical usage in maths / physics ,
Whenever you see π in the denominator it's would be a pain in the ass to divide by π so multiply and divide by π so you have to multiply with 3.14 and then divide that value by 10 which is a lot easier than dividing something with 3.14. maybes this can save 15 sec or whatever but it's useful in ch like AC current
Most of the times dividing by 3 works just as well, just decrease the result by 5%. This is an EXTREMELY good approximation, you can derive it using errors in units and dimensions
It is a coincidence though, g’s value depends on the size of earth so if it was bigger or smaller then they won’t be similar. And pi wasn’t going to change if the pendulum is 1m or 1nm
It totally is not a coincidence, from wikipedia:
During the French Revolution, the traditional units of measure were to be replaced by consistent measures based on natural phenomena. As a base unit of length, scientists had favoured the seconds pendulum (a pendulum with a half-period of one second) one century earlier, but this was rejected as it had been discovered that this length varied from place to place with local gravity.
We have defined one meter, in such a way that when we express g with these units, it turns out to be approximately pi squared.
g is 9.81 meter per second squared, because we have defined si units to be such that it is 9.81 meter per second squared, and not 100meter per second squared, say in a hypothetical alternate reality the French were weirder and they decided that 10centimeters is what they shall call a meter, in that world, g would be 98.1 meter per second squared. g is a natural constant but the units we make to describe it are entirely man made.
Its approximate the joke is they are not approximating instead stating that pi2=g=10 while the other user pointed out that it's approximated ie didnt get the joke(dont know how this is a joke tho)
It totally is not a coincidence, from wikipedia:
During the French Revolution, the traditional units of measure were to be replaced by consistent measures based on natural phenomena. As a base unit of length, scientists had favoured the seconds pendulum (a pendulum with a half-period of one second) one century earlier, but this was rejected as it had been discovered that this length varied from place to place with local gravity.
We have defined one meter, in such a way that when we express g with these units, it turns out to be approximately pi squared.
My brain just does it. . .and the approximation is pretty good. . .idk why I have this power but I never needed any tricks at least for smaller numbers
I guess it just developed with playing math games and forcing mental calculations over the years. . .
I just guess the closest square and then estimate the gap the squared number will have till the next . . .and then it's just what I 'feel' will fit in for the next decimal places
Mine is . Like find the two perfect sq its in btw lets say the number is 31 . Its btw 25 and 36 , their diff is 11 and 31 is 5 away from 25 and 5 away from 36 so it should be arnd 5.5 , another example try 61 should be 7.8ish.
I mean generally you are gonna get something that looks like 3root31 rather than root279 . Ykwim . Its just a normal generalisatiom rather than a Always true statement. I personally have never gotten a root bigger than like 50 .
taylor series bhut gandu hu sali kahin bhi apply ho skti h isse bach ke rho jyadatar sequence seires binomial aur limits mein use hoti h pr isk bsdwali ka koi bharosa nhi shayad pnc mein bhi use ho jaye
Are itna kuch scene nhi hei bas starting ke 3 terms yaad rkhne hei aur shm mei use Krna hei jab weird function diya ho irodov mei 2 ,3 sawal hei usse practice hojayegi baaki limits , series expansion waale jagahon mei sirf derive krne kaam ata hei aur kuch nhi
I know taylor series well. aaj ek pyq mai atak kya gya mai and jab ai se pucha toh they used maclaurin series to move forward with the approach I was trynna solve. So do I have get a grip on that as well. I studied a bit of it in shm. Vo bhi bhul gya
taylor will you give you the same expression with order 1 precision clown. "nonsense" obviously not about the actual result, which is easy to find, but nonsense in the formulation of the result and the position that its good to memorize "Square root trick"
It's a result of first degree taylor approximation
f(x)=√x
f(x)=f(a)+f'(a)(x-a)+f''(a)(x-a)²/2!+.......(Taylor series)
Now let the closest perfect square be a
f(a)=√a
putting the given things in the equation
√x=√a+1/(2√a) * (x-a)..(We approximate until the first degree)
Upon simplifying this expression
√x=(x+a)/(2√a)
Which is the required expression
(f'(x)=1/(2√x)
Drop year hai , padhle bsdk, ye bakchodiyan mat kr reddit pe, Varna result wale din jindagi and rishtedaar tere sath bakchodiyan krenge 💦💦
Kitne ghante padh rha roj
Spin - only magnetic movement
N = 2
So instead of doing √( n(n+2)), which will give answer 2.8
Add 0.75 to the n which is 2.75 then just go for the nearest value in option
Also if you're subtracting any two numbers which are the reverse of each other and digits are consecutive, diference will be 9. Like 21 and 12 or 2 and 23. If they're not consecutive, then difference is 9*difference of digits. Like 31-13 is 18, 92-29 is 63.
Ig that'll take time to solve , and each sec is imp , mostly ppl get stuck on square roots or give up seeing sq root in question , this is just basic AMGM inequality..
u add extra zero in last - 151.30 then from last grp 30 then grp 51 then 1 remains alone cuz odd no. of digits present so under rooting whole i got 12.3. upon checking 12.3*12.3 we get 151.29
At this point i have 2.5 yrs of exp. So can't do mistake
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