3:37 i think you meant to say you rounded not truncated :)
@AndyMath5 ай бұрын
Oh no! You are right! I messed that up...
@bebektoxic21365 ай бұрын
I see, that's why I'm a bit confused 😂
@EAOO5 ай бұрын
@AndyMath all good, love the videos!
@insaneclips11844 ай бұрын
Truncated means rounded off. Both are same dear
@EAOO4 ай бұрын
@@insaneclips1184 no, truncated means you cut off additional digits (usually decimal). So 76.73 would truncate to 76 but round to 77.
@iTube4U5 ай бұрын
everyone is gangsta untill log shows up
@faizaanfazal4 ай бұрын
True af
@HableGiday4 ай бұрын
Perfect comment😂😂
@hasandhrolia83534 ай бұрын
Kids!!
@hellboysp72633 ай бұрын
bro lowkey
@russellthescout96393 ай бұрын
log is taught in 9th grade though. it's just BAP.
@T100Tyrant-xh7ph4 ай бұрын
My mind after 0.00000001 seconds of looking at this equation : Log Log Log Log
@Aman_Gupta04 ай бұрын
fr same
@abatall4 ай бұрын
idek what log is i'm doing alg 1 rn
@yotzexotadrogue4 ай бұрын
Fr
@progisloveprogislife45014 ай бұрын
It's the opposite of exponenciation, your x in a logarithm is the exponent you need to give to the base (10 in this case) so that the result is equal to 80 (which is called the argument I think). Not that hard to grasp as a concept
@chaabomed4 ай бұрын
Exactly! Log from line 1
@kartikmaher54 ай бұрын
India's secondary school students be like,"like, seriously‽."
@tanishthakur74 ай бұрын
Really!!
@unknownfbk4 ай бұрын
Yep, its kinda easy
@D402S4 ай бұрын
Mein timepass karne KZbin mein aaya aur yaha aake yeh problem solve karne baith gya 😂
@evilgaming78604 ай бұрын
Even though it is easy for us it may not be the case for whole India. So we should not be full of ourselves.
@shashankyadav57034 ай бұрын
So true
@Jack_Attack12345 ай бұрын
Before even watching the video I know I'm gonna hear "Lets put a box around it" and "How exciting". Almost forgot the “Nice” every time 69 or 420 shows up. And you can’t forget the “this looks like a fun problem” when the video starts.
@ianyoon73365 ай бұрын
how exciting
@frankstrawnation5 ай бұрын
This looks like a fun comment.
@outerspacedog5 ай бұрын
it’s pure hype
@mzoxololinda84085 ай бұрын
And it looks important, so let's put a box around it 😅
@englishsong83995 ай бұрын
Or one can just use log
@canonogic5 ай бұрын
Idk why, but this felt like pulling off a combo KO in YuGiOh
@Redawesomeoby5 ай бұрын
Bro why ain't I ever thought bout learning math as learning combos in fighting games dawg
@canonogic5 ай бұрын
@@Redawesomeoby Hadouken to find x 😂😂😂
@RealReen5 ай бұрын
Kinda boring, but you can solve this almost instantly using log(a^b)=b*log(a)
@sauten25654 ай бұрын
Yeah that’s what I was taught but I guess the way he does it can be understood better by most people
@RealReen4 ай бұрын
@@sauten2565 true and it also demonstrates far more, useful rules.
@sauten25654 ай бұрын
@@RealReen fax, how far have you gone in maths education, like A levels or further?
@RealReen4 ай бұрын
@@sauten2565 I'm not sure how it applies to your levels, but danish A-level, and I will be having a lot of maths a uni soon.
@Livvv_happy_372724 күн бұрын
Can you show the whole working
@HurricaneZ4 ай бұрын
I tried solving it before the video, ended up with the same answer. I just did the log base 2 of 40 first to get the exponent bases to 2. got something around 5.32. set the exponents = to each other due to same bases and boom basic algebra to get to the same decimal answer. (with calculator ofc) nice video tho man 👍
@ShmizzadАй бұрын
Of course it’s because we have 10 fingers, not because we count in base 10. I see we’re skipping the intermediate steps now
@kae48814 ай бұрын
i did it by applying log to both sides, and then solving. it makes it easier because after that its just manipulation. but you do need the value for log 2 and log 40.
@vaibhavgupta86814 ай бұрын
Need to know just log 2. log 40 would be log 4 + log 10 . Everyone knows log 10 value and log 4 would be 2 × log 2.
@craigk.gowens75345 ай бұрын
My math teacher in high school wouldn't have allowed log 80 as an answer because it can be reduced like square root of 80 can be reduced. Because it is base 10, log 80 = log 10 + log 8 since log ab = log a + log b if the base is the same. Log 10 = 1, so log 80 = 1+ log 8.
@adwaitpandey25265 ай бұрын
1+3log2 which is approx 1.9
@gregstunts3475 ай бұрын
Depends, sometimes it’s the opposite. With a class that I was in, they would want me to write 1 + log 8 as log 80. But log 8 on its own would need to be simplified to 3log 2.
@mr.turtle3755 ай бұрын
Wonderful explanation.This man can teach us faster than a professional professor.
@frommarkham4245 ай бұрын
I think he is a professional
@euloge9965 ай бұрын
He is a teacher
@FylinB5634 ай бұрын
A professor is inherently a professional
@shivambharadwaj95804 ай бұрын
Definitely a middle school teacher @@euloge996
@TheBiggerNoise5 ай бұрын
I’m having flashbacks to helping my daughter with Algebra 2 😮 I love how you manage to keep the presentation so brisk, yet also don’t have any mystery steps.
@abeonthehill1664 ай бұрын
An excellent demonstration ! That was clear and easy to follow. Thanks for sharing !
@sm_artx27 күн бұрын
For the people trying to show off your logarithmic skills, Andy intended this problem to be understood by those who aren't really familiar with log. So, instead of using log identities from the get-go, he used log only when the equation was already simplified. You and I may be familiar with log, not everyone is.
@SaidVSMath5 ай бұрын
Hey Andy, unsure if you check the comments, but what software do you use to animate your videos? Thanks!
@frankstrawnation5 ай бұрын
He said that a very few videos ago.
@4.0.45 ай бұрын
I should start writing down these equivalences.
@karlkarlson35025 ай бұрын
*IMAGINE HOW MUCH NERD GIRL POON THIS GUY GETS*
@ArnaldoMandel5 ай бұрын
Quite silly, could have applied log base 2 at the outset and just solved thelinear equation.
@Reaper-jr7sz4 ай бұрын
I did this problem a whole different way and still got 1.903 as a answer
@ethastum3 ай бұрын
You could also solve this problem using logarithmic properties: 1. We take the log() of both sides, which allows us to put the exponent as a factor to the logarithm of the base. Giving us: "(x-1)log(40)=(2x+1)log(2)" 2. We multiply into the parenthesis on both sides, and isolate the terms with x in them. Giving us: "x log(40)-2x log(2)=log(2)+log(40)" 3. We isolate x by factoring, and dividing the resulting parenthesis to the right. Giving us: "x = (log(2)+log(40)) / (log(40)-2log(2)) 4. Due to the rule of logarithms used in (1), we can express the "2log(2)" as "log(2^2)" which equals "log(4)", whereafter we use the rule of sums and differences of logarithms. Giving us: "x=log(80)/log(10)" 5. Due to log-base10 of 10 being 1, this gives us the result as: "x=log(80)"
@adaaaa66425 ай бұрын
I solved it in seconds just multiplying entire equation with log10 and got answer without calculator. Anyone with log knowledge can do it.
@olivier.st-amand5 ай бұрын
A video about a list of the usual "tricks" that can be used in such math problems (like the 30-60-90 triangle, the exponent substitutions you used here, etc...) would be amazing! Thanks!
@kharshithaashree74474 ай бұрын
Easy method here Just take log on both sides and multiply it in side then you should have an equation with both sides having x of power one and substitute values of log40 ( log4 +log10) and log 2 Then u get 1.602x-1.602=0.601x+0.301 On bringing x oneside and constant on other side u get 1.001x=1.903 Which is approx answer x=1.903 If you need more precise then increase the decimal numbers That's it not even a 2min task
@aadityasrivastava164 ай бұрын
That's what i was thinking it took me about 1 min to solve this mentally i was like he must have asked a numerical value i solved log 8 ans 3log2 = 3X.30 and i got 1.90
@papawoolliest42324 ай бұрын
“Log 10 means the same thing as log, and the reason for that is we have 10 fingers” Wh… what?
@joeyd93514 ай бұрын
Everything is base 10 unless otherwise stated. I'm not sure if our amt of fingers is the reason for that, but maybe it is
@terakhanthis13 күн бұрын
So, just for the sake of it, 40 is equal to 2^5.321928. If I understand powers right, this would give: (2^5.321928)^x-1 = 2^(2x+1) 2^(5.321928x - 5.321928) = 2^(2x+1) 5.321928x - 5.321928 = 2x+1 3.321928x - 5.321928 = 1 3.321928x = 6.321928 x = 6.321928/3.321928 x = 1.90309
@SRINIX4356Ай бұрын
Hi man! What an amazing video! But, the verification can be done like this without a calculator: 40^(x - 1) = 40^(log80 - 1) = 40^(log8 + log10 - 1) = 40^(log8 + 1 - 1) = 40^log8 2^(2x + 1) = 2^(2log80 + 1) = 2^(2(log8 + log10) + 1) = 2^(2(log8 + 1) + 1) = 2^(2log8 + 2 + 1) = 2^(2log8 + 3) = 2^2log8 * 2^3 = 4^log8 * 8 = 4^log8 * 10^log8 = (4*10)^log8 = 40^(log8) here, we can see that 40^(x - 1) gave us 40^log8 and 2^(2x + 1) also gave us 40^log8. so, verified.
@kmktruthserum93284 ай бұрын
I knew that because I brute forced and put 1 as x and 2 as x and then just did 1.5 and kept raising it to 1.9.... They need to make it a bigger x so that I can't just input numbers quicker than it takes to actually use the correct formulas😅
@Dinglebeardedlady5 ай бұрын
I usually have the answer in my head before he finishes the countdown. ...then I watch the video to see HIS process and what the right answer is.
@ananasanimator60495 ай бұрын
Решил по формуле Пика за 0,000000002 секунды
@frustationoverloaded59764 ай бұрын
by trial and error i found 1 then 2 then 1.9. and 1.9 is way way too close. I found in 3rd iteration via calculator. I will take that as ok becuz in real life that would negligible difference, mostly covered by buffer and in real life u won't be fucking sitting there finding value of log 69 or something. Maths doesn't has real life applications beyond class 10 or 12 . Edit: the answer is 1.90309 lol That's 0.16 % difference.
@rocky1010163 ай бұрын
would it be incorrect to just take the root of x-1 to both sides, which means the 40↑x-1 becomes 40, and the 2↑2x-1 becomes 2↑x and solve from there?
@Eric-cz1er4 ай бұрын
From 1st sec, i striaght knows that just using ln() then find the x. Just that simple. No need to be simplify🤔 why need sinplify as we can just using ln() loll
@aviationkidd53803 ай бұрын
if u try to compare the exponential powers it gives us the result as 2 which probably is a good approximation pls correct me if i'm wrong thanks :)
@starboy001Ай бұрын
I arrived just after studying logarithms. And now this time it is again equality more exciting as always.
@aram56425 ай бұрын
I thought it was because we have 10 toes
@peace01734 ай бұрын
Without using log i some how by unitary method only i got two values of x which are 1 and 4 and this not possible and my method was also not wrong.
@sp_ahmed89974 ай бұрын
why didn't you just ln the both sides from the first ? it would've been much easier.
@Epyxoid3 ай бұрын
2:31 I think explaining that with the inverse function is more logical. Just like in _tan x = 2_ we take the inverse function of _tan_ on both sides, which is _tan^-1_ that gives us _tan^-1 (tan x) = tan^-1 (2)_ which simplifies to _x = tan^-1 (2)_ Here, the inverse function of _10^x_ is _log 10 (x)_ Taking that on both sides gives us _log 10 (10^x) = log 10 (80)_ which simplifies to _x = log 10 (80)_
@praveensrivastava.52534 ай бұрын
Who solved this problem without using pen like me 🗿🗿😎
@aryawijayaa954 ай бұрын
Yes i solved it,without seeing it😎 No u are lying i didn't believe
@praveensrivastava.52534 ай бұрын
No bro, I'm studying in class 12
@tunneloflight4 ай бұрын
if you apply significant digits - the answers are the same
@Chewy4275 ай бұрын
i knew the answer would be in terms of log, so kinda disappointing
@Latif12874 ай бұрын
I solved it in another way and i found the same result as yours, i am more happy to send it to you if you want to see how
@MarcoPolo-bn9qr3 ай бұрын
Yay!!! I do it before of seeing the video and I got it right🎉🎉🎉
@haianhngo1135 ай бұрын
that too easy with 16 years old vietnamese people =))
@englishsong83995 ай бұрын
Is nobody going to say how easily it could have been solved by using log
@dow_wob5 ай бұрын
so simple you just know about log 5on2 =2.3 and done and solve it but you can do it simple you should change this log to log5 /log2 => 0.7/0.3 =2.3 (rounded ) and you dont wana calculator or somthing this question was standard for student
@ViReel94364 ай бұрын
Shouldn't a and b from the LHS and RHS be same?
@jackmoore26364 ай бұрын
I got ln(80)/ln(10) but it came out as the exact same thing, beauty of maths, different kinda methods but same answer if you do it right.
@smallgamer78814 ай бұрын
just introduce logs to both sides in the beginning 40^x-1=2^2x+1 log 40^x-1= log 2^2x+1 power law of logs, the power of the log can become the coefficient of the log (x-1) log 40 = (2x+1) log 2 x log40 - log40 = 2x log2 + log2 move the x terms to the left, and the log40 to the right x log40 - 2x log2 = log 2 + log 40 factorise x from the right x(log 40 -2log2) = log2 + log40 x= (log2 + log40) / (log40 -2log2) = 1.903089987
@TrollSilver.4 ай бұрын
You can also be silly and just find 2 to the power of what is 40 (comes out to 5.2319) and then finding x
@chitreshbhati98825 ай бұрын
why don't you apply LOGARITHM on both sides
@jozeppelachetti71374 ай бұрын
I checked this equation with gpt, the first answer for x=4. Then I asked to recheck and it was able to find the same answer but using log2
@suhaibalkhaldi3 ай бұрын
i used the natural log from the first step
@diazlard5 ай бұрын
This could be much simpiler. Use a logarithm to find what exponent makes 2 = 40. Expand that through x-1. Use algebra to find x.
@svxxrrz4203 ай бұрын
This is the first time I watch your videos and honestly they're actually helping me understand math even better, I don't know, I try to resolve the problem a little faster than you just to see if I can do it, sometimes I get it wrong but it's fine, I keep trying, thank you! you're helping someone get better at math!
@Emilia333g4 ай бұрын
Doing this myself before watching the video was weird, it didn't feel right to get such a nice result.
@reelkanha3 ай бұрын
bruh nvm WHY YOU USING CALCULATOR!!!!!!!!!!!!!!!!
@reelkanha3 ай бұрын
as a ninth grader, anything after 2:31 is witchcraft
@mashhudaparveen64753 ай бұрын
It took a minute for me to slove. Aaah.....
@Anurag_2.0Ай бұрын
x=1.9 => (x-1)log40 = (2x+1)log2
@user098325 ай бұрын
Take log in the first step; (x-1)(2log 2 + log 10) = (2x+1) log 2 => 2x log 2 - 2log 2 + x -1 = 2x log 2 + log 2 => x - 1 = 3(log 2) => x - 1 = 3(0.30103) => x = 1.90309
@samir2zk1355 ай бұрын
That's more what I was thinking lol, how they show us in school. xd
@sietsevanderhorst81445 ай бұрын
''its because we have 10 fingers''
@lt.turtle32684 ай бұрын
(Ln80)/(Ln10) gang
@Sg190th5 ай бұрын
yeah, log can work. I just prefer natural log because it looks easier to format in my opinion.
@rathersane5 ай бұрын
But when the base is already 10…
@Grizzly01-vr4pn5 ай бұрын
How (and more importantly why) would you crowbar ln into this?
@Sg190th5 ай бұрын
@@rathersane You can use logarithm regardless but yes, it's usually 10 as base. In this case, it works better. I'm just saying what I prefer in my opinion. Is that bad?
@Sg190th5 ай бұрын
@@Grizzly01-vr4pn Crowbar? Huh???
@rathersane5 ай бұрын
@@Sg190th No… It just seems like more work in this particular case.
@Tmwyl4 ай бұрын
Because we have 10 fingers! 😂
@nabil43895 ай бұрын
Andy!!
@irmabecx47585 ай бұрын
iIs the reason for that really that we have ten fingers??
@shakhawatparvez87054 ай бұрын
As an Asian parent I would say this should be easy for my 2 year old one
40^(x-1) = 2^(2x-2) would be more of an interesting problem: (x-1)ln40 = (2x-2)ln2 xln40 - ln40 = 2xln2 - 2ln2 xln40 - 2xln2 = ln40 - 2ln2 x(ln40 - 2ln2) = ln40 - 2ln2 x = (ln40 + ln2) / (ln40 - 2ln2) x = 1
@FarzadFarhad-ur7xd4 ай бұрын
There was a really easier way, you could write as (2^ 5.32192809490)^x-1=2^2x+1 ,since both bases are the same we can write down as 5.3219280949(x-1)=2x+1 which is then equal to 5.3219280949x-2x= 5.3219280949+1 then x= 6.3219280949/3.3219280949
@nonsoottih74054 ай бұрын
Anyone else found this hella easy?
@venca20243 ай бұрын
man I'm 14 my head hurt
@Redditstoriesbyme5 ай бұрын
You could have done a 2nd level unknown equation to get it without a calculator
@adityamodi49654 ай бұрын
Why i always want to take log😂
@Voiceistic-kl3ki4 ай бұрын
I'm in 10th class from imdia and solved it very easily
@maincoasters4 ай бұрын
i’m in 6th from the usa and solved it really easily
@dijendrakalita75025 ай бұрын
i got x = 1 + 3log2
@Abhi-lz6zo4 ай бұрын
Log 2 equals 0.30 and 3 times log2 is 0.90 adding one to it will result in 1.90....the answer is same
@llll-lk2mm5 ай бұрын
im so happy that i could figure this one out in the thumbnail itself heh yay
@elbayo4215 ай бұрын
No base drop = thumbs down
@hilariousroom31814 ай бұрын
Couldnt u do on comparing powers?
@purnashreechatterjee56914 ай бұрын
I got it right somehow 💀
@CleanYourSkullDaily4 ай бұрын
… no clue how I got x = 1
@Eclectic-empire4 ай бұрын
Indeed that is how is supposed to be done, 👍
@user-lynKx4 ай бұрын
wolfram here we come
@RobG17295 ай бұрын
It'd be cool for you to make videos about our ten fingers and base 10 number system versus others like base 12. I'm sure those too would be exciting.
@NaveenThiagarajan5 ай бұрын
Approximately 2, right?
@metaphoricalhuman4 ай бұрын
Great video, it randomly appeared in my recommendations and i'm having a test on this exact stuff this week
@mustfar4 ай бұрын
I got 1.8 😢
@Fuzierka5 ай бұрын
in the USSR, children solved such examples in nurseries
@samir2zk1355 ай бұрын
IMO childrens thinking capabilities way more powerful. Age won't matter, IG time does.
@krewmermore33245 ай бұрын
What a smart and simple way to solve it by rules of indices 😻
@jonathantheyorkie4 ай бұрын
I'm used to the ones that share a common base
@francoismusic_5 ай бұрын
Can I send you a problem?
@viktoraxa89634 ай бұрын
My way was way more complicated 🥸 My first step was log40(40^(x-1))=log40(2^(2x+1)) Then (x-1)(log40(40))=log40(2^(2x+1) x-1=log40(2^(2x+1)) x-1=(2x+1)(log40(2)) x-1=2xlog40(2)+log40(2) x-2xlog40(2)=log40(2)+1 x(1-2log40(2)=log40(2)+1 x=(log40(2)+1)/(1-2log40(2))=~1.9
@CharashGanja4 ай бұрын
Lol i sloved it in my head 😅😅
@allayhok5 ай бұрын
Nice
@ngneerin5 ай бұрын
It's log more exciting
@qazsedcftgbhujmkolp44015 ай бұрын
Did he do this one right?
@gamingplus86255 ай бұрын
@andymath what kind of training do you do for your deep voice?