#help-42
1 messages · Page 73 of 1
What do u mean?
yes?
In the part I circled
Like is there supposed to be another line there or is it right
also how can i find the point of intercepts for f(x) = 6- x^2 and its inverse root 6-x
U dont neef to prove it
Its a fact
Those x value has a corresponding f(x) and they're there
Oh that ones for a different question
Sorry well start a new question
how can i find the point of intersection for f(x) = 6- x^2 and its inverse root 6-x
Like the intersection of the 2 lines?
yeah
oh sorry no like
f^1(x) = root 6-x
so originally i found the reciprocal of 6 - x^2
and got that
the next step was the point of intersection
yeah
Just set them =
i also substituted for y and got x^4 + 12x^2 + x +30 = 0
6 - x^2 = sqrt(6-x)
yeah i wasn't able to factorise it
square them
yeah and then i got x^4 - 12x^2 + x +30 = 0 is what i mean
and wasn't able to factorise it
Use calculator then
is there any like way to do it without calculator?
its a 4 degree poly
yeah so 4 intersections
Only 2
U need to restrict that sqrt
would you have a plus minus in front of it
okok
wait so
im a bit lost
i squared the square root meaning i squared both sides
and then i brought everything to the LHS
and got x^4 - 12x^2 + x +30 = 0
but im not sure how to solve for x so i can then substitute it and find y
unless this process is wrong
@polar frost
Just use the calculator for this part
then u should get 4 values of x
but u should only accept x > 0
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Option 1: 2(lw + lh + wh), l + w + h, lwh Option 2: 3 layers of 10, 7 layers of 21, 3 layers of 21, 7 layers of 3. Option 3: volume, edge lengths, base area Option 4: equal to, less than, greater than
Image
pls help 🙂
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could i possibly get some help on this question? i'm just honestly quite confused on where to even start with this
also be aware of the fact that rainfall cannot be negative
yeah i'm just confused on the > thing but should i just treat it as = when solving for x?
Doesnt matter
kind of yeah, but you also swap the direction when multiply both hand side with negative
For that function y>60 only return x in positive
the problem is just convenient to give that result
without considering it, the answer is inconplete
wait so i should write it out as 60 > 7500x/x^2 + 2500?
i'm just confused because the final answer is a range
there is some algebra you have to do
so like, do you understand that [
\4{7500x}{x^2+2500} \ge 60
]
is the inequality you are meant to solve
yes
ok
so a good way to start is to subtract 60 from both sides, and combine everything on the left to a single fraction
What does that get you
oh i thought it would be better to multiply each side by x^2 + 2500 to cancel out that fraction
I would say its easier to multiply both sides by x^2+2500
i mean sure the denominator goes away either way
yeah
note that x^2+2500 is certainly >0, so you dont have to switch the inequality
so then i got that 60x^2 + 150000 < 7500x
yeah
or wait i can just send what i did
i know i should've put < instead of = but yea
i still don't think i got the right answer idk
maybe i'm stupid but i don't know what's wrong with that
You should use the => arrow instead of -> this one
I thought u were substitute that part in
oh i didn't know that made a difference it's just kinda how i write stuff down for myself when working out
😭
it's not really important its fine, you can always just include the endpoints
Hmm
anyways
im pretty sure you erased a 0 from the 150000 @mortal heath
Did u remove one 0 from 150000 to 15000
oh i did my bad 😭
Wait no
i got it thank you!!
Did she devide everything by 10
i did yeha
yeah i did
my mistake was that i calculated with 1500 instead of 15000
i got the right answers fixing that haha
yeah she erased a 0 like we said lmao
thank you! sorry if this work is really simple but i appreciate the help a lot 😭 need to pass this class
2 values of x mean u need to limit it
Good
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Please help
you can solve for x since the all the probabilities sum to 1
split that thing into P(B intersect A')/P(C)
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where?
On the penultimate line of the photo
this?
Yes
like to go from the line above it to that?
Yes
well in general no
you should combine LHS into a single fraction
then cross multiply
LHS has common denom already
don't simplify the 3^(n+1)/3^(n+1) part
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working on triple integrals! what am i doing wrong here?
Something’s wrong why are you integrating over T but then you say a ball B
oops
forgot that i wrote t
should be b
nothing else is changed i just had T in my notes and instinctually put it there
im confdent theres something wrong with the setup
I don’t see it soz I’m very sleepy tho
all good
im guessing its a dumb mistake somewhere i havent seen
Yup
forgot rho ^2
lmao
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Hi
Please show your work in future
I calculated it.
I know but the steps are also important
It saves us from having to do your work again
It is much easier for us to fix your error from your work. It doesn't really help you if I just give you the right answer right?
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I split this into
$\int_{\frac{1}{3}}^{\frac{1}{2}}e^2dx+\int_{\frac{1}{2}}^1edx+\int_1^3dx$
ƒ(Why am. I here)=I don't know
would that be right
if right that would be
$\int_{\frac{1}{3}}^{\frac{1}{2}}e^2dx+\int_{\frac{1}{2}}^1edx+\int_1^3dx=e^2\left(\frac{1}{6}\right)+\frac{e}{2}+2$
ƒ(Why am. I here)=I don't know
Did you remember the ln part
,w 2(1/2-1/3)+(1/2)
so $\int_{\frac{1}{3}}^{\frac{1}{2}}\ln\left(e^2\right)dx+\int_{\frac{1}{2}}^1\left(e\right)dx+\int_1^30dx=e^2\left(\frac{1}{6}\right)+\frac{e}{2}+2$
Yeah e^2 should be replaced with 2 and so on
ƒ(Why am. I here)=I don't know
thanks!

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✅
so I was thinkng of solving this by. breaking it down into seperate intervals
$\int_0^1xdx+\int_1^22x^2-1dx+\int_2^33x^3-2dx$
ƒ(Why am. I here)=I don't know
would that be right
Yeah
thanks!
Max
hmm
let me think
thanks for the nice problem
hmm
so that would be
$e^0+e^{-1}+e^{-2}....$
ƒ(Why am. I here)=I don't know
yea
$\frac{e}{e-1}..$
ƒ(Why am. I here)=I don't know
yea
thanks! That was fun
if u like integrals
there are Bees such as the MIT int bee and UK Integration Bee (Cambridge)
I do solve them, that's where I get these problems from, Thanks though!
could you link to the cambridge bee
can't find it
saw this in the caltech one lol
it is from the caltech one
utilize symmetry about pi/2 
$\left(\int_0^{\pi}\frac{\left(\sin\left(\frac{x}{2}\right)-\cos\left(\frac{x}{2}\right)\right)^2}{\left(\sin\left(\frac{x}{2}\right)+\cos\left(\frac{x}{2}\right)^2\right)}dx\right)$
ƒ(Why am. I here)=I don't know
after some simplifcation it turns into tan^2(x/2) which is easy to integrate
oh lord

If we’re doing integration then have another fun one
Hint: ||binomial theorem||
thanks!
thanks!
do you know how to get there
thinking about it
alright
this could be converted to $\int_0^{\pi}\left(\tan\left(\frac{\pi}{4}-x\right)\right)^2$
ƒ(Why am. I here)=I don't know
which is integrable
fair
3 more random ones I had lying around, I’ll leave you alone now
👋
thanks a lot
for the 19th one ||you can split it as arctan(1 + x) - arctan(x)||
and the 20th is just ||an embellished euler log trig so thats -pi(ln 2)/2||
spoilers !
👍 feel free to ping me if you want more
this is $\int_0^{\frac{3\pi}{4}}1-\sec^2\left(x-\frac{\pi}{4}\right)+\int_{\frac{3\pi}{4}}^{\pi\ }1-\sec^2\left(x-\frac{\pi}{4}\right)$
ƒ(Why am. I here)=I don't know
thanks!
which evaluvates to
$\int_0^{\frac{3\pi}{4}}1-\sec^2\left(x-\frac{\pi}{4}\right)+\int_{\frac{3\pi}{4}}^{\pi\ }1-\sec^2\left(x-\frac{\pi}{4}\right)=\frac{3\pi}{4}-\tan\left(\frac{\pi}{2}\right)+\frac{\pi}{4}-\tan\left(\frac{3\pi}{4}\right)-\tan\left(\frac{\pi}{\left(2\right)}\right)$
ƒ(Why am. I here)=I don't know
what am I doing wrong here
oo
it should be x/2
$\int_0^{\pi}1-\sec^2\left(\frac{\pi}{4}-\frac{x}{2}\right)$
ƒ(Why am. I here)=I don't know
whcih is $\pi-1$
ƒ(Why am. I here)=I don't know
now onto these
$\left(\int_0^{\infty}\tan^{-1}\left(\frac{\left(x+1-x\right)}{1+x\left(x+1\right)}\right)\right)$
ƒ(Why am. I here)=I don't know
why do you surround the whole thing in parenthesis lol
dunno what that means but alright
$\int_0^{\infty}\tan^{-1}\left(\left(x+1\right)-\tan^{-1}\left(x\right)\right)$
ƒ(Why am. I here)=I don't know
whatever your approach 0 is
which can be integrated by parts
its misplacing parenthesis willy nilly
Approach Zero: A math-aware search engine.
that's my doing
lol the whole thing is in an arctan
$\int_0^{\infty}\tan^{-1}\left(x+1\right)-\tan^{-1}\left(x\right)$
ƒ(Why am. I here)=I don't know
,w $\int_0^{\infty}^{-1$\ln\left(x\right)\arcsin\left(x\right)-\int \frac{\arcsin\left(x\right)}{x}$$\int \frac{\ln\left(1-x\right)}{\sqrt{2x\left(1-x\right)}}$}\left(x+1\right)-\tan^{-1}\left(x\right)$
lol
thanks
use arctan
yeah, will in the future, I think in this problem, getting it to this form was the hard part, so I'll skip evaluvating it for now
onto problem 20
$\int_0^1\frac{\ln\left(x\right)}{\sqrt{1-x^2}}$
ƒ(Why am. I here)=I don't know
let $x=e^t$
ƒ(Why am. I here)=I don't know
$\int_1^e\frac{te^t}{\sqrt{1-e^{2t}}}$
ƒ(Why am. I here)=I don't know
-infinity to 0
ƒ(Why am. I here)=I don't know
$\int_1^e\frac{te^t}{\sqrt{1-e^{2t}}}=t\sqrt{1-e^{2t}}-\int \sqrt{1-e^{2t}}$
ƒ(Why am. I here)=I don't know
$\int_{\ -\infty}^0\frac{te^t}{\sqrt{1-e^{2t}}}=t\sqrt{1-e^{2t}}-\int \sqrt{1-e^{2t}}$
ƒ(Why am. I here)=I don't know
let $e^t=u$ for the second part
ƒ(Why am. I here)=I don't know
I think I;ll just be going in circles if I do that
the IBP is
let me IBP instead
not right 
i mean as it stands for t --> - infinity you don't even get a real answer
$t\arcsin\left(e^t\right)-\int \arcsin\left(e^t\right)$
ƒ(Why am. I here)=I don't know
you'll have to do some limit fuckery
I think I better IBP the first function instead
easy enough though just multiply and divide by e^t i'd think
this
sure try it out
$\ln\left(x\right)\arcsin\left(x\right)-\int \frac{\arcsin\left(x\right)}{x}$
ƒ(Why am. I here)=I don't know
,w integrate arcsin(x)/x
oo
F
ƒ(Why am. I here)=I don't know
nah
that won't work either
hmm, maybe I use a polynomial approximation for bith functions
and integrate that
you cant approximate this stuff
hmm
the choices are all closed form
ƒ(Why am. I here)=I don't know
let $ln(x)=u$
ƒ(Why am. I here)=I don't know
yes please
trig sub
hmm, x=sin(t)
so dx=cos(t)dt
$\int \frac{\ln\left(\sin\left(t\right)\right)}{\cos\left(t\right)}\cos\left(t\right)dt$
ƒ(Why am. I here)=I don't know
oh
hmm
ok
hmm
$\int_0^{\frac{\pi}{2}}\ln\left(\sin\left(t\right)\right)+\ln\left(\cos\left(t\right)dt\right)$
ƒ(Why am. I here)=I don't know
this is 2I
is it -pi/2 ln(2)
$\int_0^{\frac{\pi}{2}}\ln\left(\sin\left(t\right)\cos\left(t\right)\right)dt\ $
$\int_0^{\frac{\pi}{2}}\ln\left(\frac{\sin\left(2t\right)}{2}\right)dt\ $
$\int_0^{\frac{\pi}{2}}\ln\left(\frac{\sin\left(2t\right)}{2}\right)dt$
no space after the last character
yeah
ƒ(Why am. I here)=I don't know
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the denominator's form looks similar to this
oh i see 
1 + x + x^2 in the denominator always screams a sub
ƒ(Why am. I here)=I don't know
not what I meant but keep going 🫠
first keep going with what you were thinking 
$\int_0^{\frac{\pi}{2}}\frac{\sec^2\left(u\right)}{\sec^2\left(u\right)+\tan\left(u\right)}$
ƒ(Why am. I here)=I don't know
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$\int_0^{\frac{\pi}{2}}\frac{u\sec^2\left(u\right)}{\sec^2\left(u\right)+\tan\left(u\right)}$
ƒ(Why am. I here)=I don't know
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nah
I'll try some other sub
$\int_0^{\infty}\frac{\arctan\left(x\right)}{\tan\left(\operatorname{arccot}\left(x+1\right)-\operatorname{arccot}\left(x\right)\right)}$
ƒ(Why am. I here)=I don't know
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nah, that won't work either
maybe I IBP

that definietly won't work
I guessing I have to do something to the denom
write it in terms of trig functions , is that right?
keep trying ig 🤷♂️
hmm
what have I returned to
$\int_0^{\infty}\arctan\left(x\right)\tan\left(\arctan\left(x+1\right)-\arctan\left(x\right)\right)dx$
ƒ(Why am. I here)=I don't know
do you wanna know what id do
I guess IBP is wrong here
did that long ago
ah this is what ur trying
$\int \frac{\arctan\left(x\right)}{\left(1+x\right)^2-x}$
ƒ(Why am. I here)=I don't know
not really imo but u can try
hmm
ok
in that case I think I have to express the denom as an inverse trig function?
that seems to be it
wdym?
this is almost in teh same form except for the tan
$\int \arctan\left(x\right)\left(\arctan\left(x+1\right)-\arctan\left(x\right)\right)$
ƒ(Why am. I here)=I don't know
oh 💀
am i right until here
i have no idea what u subbed
no sub yet
wth r u doing then 💀
just tried re-writing 1/(1+x+x^2)
that's why I wrote it as $tan\left(\arctan\left(x+1\right)-\arctan\left(x\right)\right)dx$
ƒ(Why am. I here)=I don't know
so it will indeed be this
i am trying feynman 🙂
That's way beyond me
tbh it isnt
as long as uk partial diff
which everyone knows as long as they r good at differentiation
hmm feynman gives something that i might be able to partial frac
hmm oh wait i forgot the infinity
why am I so slow, lol
ye why didnt u just that if he gave u that 💀
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well if u want i can show u the feynman way @blazing coyote
its pretty easy that way
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How do I prove this obvious statement
construct a bijection between the sets
Can the subsets have the same elements?
the subsets don't have all the same elements
One has n the other does not
A and B are different sets, they just have the same cardinality
Ok
How do I create a bijecriom
for any $A \in \mathcal{A}$ it corresponds to the set $A \cup {n} \in \mathcal{B}$
Awesam
I assume you learned how to show that sets have the same cardinality?
what did you learn as the method
Logic
so you're not looking for a formal proof just intuition?
Ye the statement is obvious
But how do I do a formal proof
Using BP
what's BP
What even is it
do you know what a bijection is
yes
And onto
Ex: {1,2,3,4,5} and {5,6,7,8,9}
yes so if you map a set $A$ to a set $A \cup {n}$ then this is a 1 to 1 correspondance between $\mathcal{A}$ and $\mathcal{B}$
Awesam
for example if I have the set ${1, 2, 3}$ then it maps to the set ${1, 2, 3, n}$
Awesam
then every set maps to a different set and every set containing n is accounted for
1,1 2,2 3,3 it’s one to one and onto
Because n has no element mapped
Surjective
I’ll show u my proof
And you see if it’s good ok?
okay
that's not onto
also that's not even what A and B look like
A is the set of all subsets not containing n
B is the set of all subsets containing n
@remote mural Has your question been resolved?
So what do I do
.
But I don’t understand that
He gave you the correspondence
.
But I don’t understand what it says tho
No
Yes you're trying to show this mapping is a bijection
So you need to show it's injective and surjective
But isn’t a bijectiom also mean it’s onto?
What does onto mean
One to one means the mapping goes 1 element for each corresponding
But onto?
Sorry I never learnt this lol
Let f:A -> B then f is onto if for every b in B, there exists an a in A with f(a)=b
if a1 and a2 are distinct
How is it obvious
Because each subset will be different
Yes but why wont f map different subsets to the same thing
The sets which hold the subsets are equal caridinality I mean
So now, how do I construct the proof
Cuz I’m still lost I can’t visualize anything
@ancient helm can u show me an example?
Let’s say i take the set X={1,2,3}
That's not what B is
Is it that?
Oh
Ok now show me the mapping
Ok
You need to show your map is injective and surjective in your proof
That’s hard there’s so many elements
How do I generalize?
Aren’t all possible subsets 2^n
?
Half contain n, half don’t
So I’ve proved it but not by BP 😂
Look I’ve never proved something using BP. I know what it is now, but I don’t know how to use it
Ok first how do I prove that it’s is invective (ie at least 1 x connects to exactly 1 y)
<@&286206848099549185> can someone tell me how to prove injectivity?
Injective is when B can only have 1 A or 0
3ndlyb Alabyd
I see but how do I connect that to the problem I need to solve?
What's the problem? I am too lazy to scroll up
@remote mural Has your question been resolved?
idk what BP is but you can pair up items in A and B to prove it
like {stuff without n} pairs with {same stuff with n added}
and that hits everything
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im having a tough time understnading logical statements and negations. could someone verify that my process is correct for these problems?
@proper panther Has your question been resolved?
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how do I solve this?
you know how log laws work right
yeah
do you think u can apply it here
so do i do ln((1+4R^2)/1+R^2))? i dont see how that helps tho
oh brother it helps
what can you do with limits here
in this situation
given that you have a inside function nested inside an outside function
Can you not push the limit inside if the limit inside exists?
inside the log?
yes
ahhh ok
you see now
mhmmm
thanks for that
np
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,w plot 1-x^2
notice how the function is symmetric about x = 0
so instead of integrating from -1 to 1, we integrate from 0 to 1 and double the value
so
its the same thing
like
i dont need to change it
but
its for
easiness
@mossy wigeon Has your question been resolved?
yes
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yo
I don't understand why f(x) is a bijection from the natural numbers to the positive rational numbers
in there example, there is never any rational number greater than 1 in there list
Because of that, isn't this a bijection from the natural numbers to all rational numbers between 0 and 1?
So why did they claim its a bijection from the naturals to all positive rationals?
you're right
an actual example for your reference, from wikipedia (note that the red numbers are duplicates and are discarded)
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I have to prove
$Z_1 \bar{Z_2} + Z_2 \bar{Z_1} = 2 |Z_1| |Z_2| \cos (\theta_1 - \theta_2)$
great!

now, is Z and Z^C complex numbers
Z1 and Z2 are complex numbers, the $\bar{}$ represents their conjugates and $\theta_1 \ and \ \theta_2$ represent their arguments respectively
fredthebread69
fair enough what did you try
I have tried putting $Z1 = |Z1|e^{i\theta}$
try using the respective form for complex numbers
$$z_1 = r_1 (\cos \theta_1+ i \sin \theta_1)$$
ℕaive
$$z_2 = r_2 (\cos \theta_2+ i \sin \theta_2)$$
ℕaive
Can I not use exponents and try?
sure if you feel so
Could you help me out?
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does the RHS look like some familiar identity/law/rule?
(idk if it's helpful actually i just noticed it immediatly)
It would help if someone knew what the name of the identity haha
And yes it's an identity
yea is it possible to visualise the LHS as what was usual in that identity?
ir transpose/convert etc
somehow idk
What?
like if u think about it the cos rule works out the square of the side opposite the angle
now u have angle and the 2 sides
can u make z1__z__2+__z__1z2 into that somehow
The cosine rule?
yea
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Let $f(x, y, z) = 14 + x^3y^4e^{x(z+4)}$ and $A = (1, 1, −4)$ \
(a) Specify the tangent plane to the level surface f(x, y, z) = 15 at point A.\
(b) At what rate of change $f′_v (A)$ does f increase or decrease in the direction (−6, 2, −3) away from the point A? \
(c) In what limits does the directional derivative $f_v (A)$ depending on the departure direction v away from A?
Merineth
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Anyhow.... i have a formula for calculating the tangent plane
Does this formula work with f(x,y,z)
or is specifically f(x,y,)
Where v is the direction
Hold on, do I just input the point A into the formula essentiallly to get the tangentplanes equation?
Yes
I don't understand what you want in (c)
No. The other one
Oh
Because the surface is f(x,y,z)-15 = 0
Vanishes when you take derivative
"In what limits varies the directional derivative $f'_v (A)$ depending on the direction of departure v from A"
Merineth
It's written in very poor swedish so a little hard to translate it 
Are you asking for minimum and maximum values of f_v'(A)?
I honestly have no idea, it's written in very poor swedish to begin with so it's quite unclear
I could ask my teacher for more clarification
Please do so. There is no point attempting a question which is unclear
either way, do i need to handle the triangle differently?
Cant remember what it's called
delta?
gradient?
themadchessplayer
Otherwise part (c) does not make sense
Yes, it is gradient. The symbol is called nabla
Oh ok! And gradient is a derivative vector?
Transpose of derivative (Jacobian) matrix
"The gradient of a line is the measure of the steepness of a straight line." seems right?
But i can't just inpout a,b,c into the fornula right?
I have to do something with the gradient?
Since we are not screwing around with weird bases of R^3.
$\nabla F(1,1,-4) \cdot (x-1, y-1, z+4) = 0$
Merineth
We can. Just calculate $\nabla f$ and plug (a,b,c) in it. The specific values ensure that the point is actually on the surface $f = 15$
themadchessplayer
the gradient of that point will give a value, right?
No!
Gradient is a vector
Oh, i thought gradient was to calculate the slopes incline / decline
Is this the one i should use ?
Merineth
x is in bold, does that mean it's a vector?
I don't have a vector, i have a point
Are you sure i can use that formula to calculate the gradient?
hi can any body help with a question for solving a differential equation?
!occupied
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@upper sparrow 
Don't worry. Boldface is often used for points in R^n.
Yes
Why is f lowercase here but uppercase on the formula for calculating the tangentplane?
That's the third or fourth time you asked this
Different places have different notations
For functions
$\nablda f(1,1,-4) = (\frac{\partial f}{\partial x} (1,1,-4), ... )^T$
Merineth
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@austere moth Has your question been resolved?
Yes do this calculation
Got a little trouble with the derivatives
$\frac{\partial f}{\partial x} = 14+x^3y^4e^{x(z+4)}$
Merineth
14 is a constant so it disappears
I think i have to use product rule here to derive x^3 and e^(x(z+4))
However i'm not sure what happens with y^4 when i try to apply product rule
$x^3y^4e^{x(z+4)}$
Merineth
Merineth
I guess i can apply the product role within the 
$\frac{\partial f}{\partial x} = 14+x^3y^4e^{x(z+4)}$
Merineth
<@&286206848099549185> Can someone please help me with deriving this expression with respect to x
I understand that the constant 14 dissapears
and that i can apply the product rule to
$y^4(x^3e^{x(z+4)})$
But i just can't seem to get the right answer...
Merineth
partial derivative of this wrt to x?
Yea
$y^4(3x^2e^{x(z+4)} + x^3(z+4)e^{x(z+4)})$
Merineth
Yeah i think
I'm not getting the same on wolf or derivator-calculator.net
,wolf derive with respect to x (14+x^3y^4e^(x(z+4)))
thats same
I tried simplifying but i'm not getting the same afaik?
pretty sure it is
glad to hear
and when i do with respect to y then it's literally the same?
except 4y^3
,w derive with respect to y (14+x^3y^4e^{x(z+4))
,w derive with respect to z (14+x^3y^4e^{x(z+4))
I did the calculation and i think i got the right answer
Does it seem right?
I never utilized 15 tho?
So i might have done it wrong?
<@&286206848099549185> :(
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hello, i am trying to prove {0,1} is an albien group under ⨁.
do you mean $\mathbb{Z}_2$?
chebyshev's infinite pee norm
yesh
because that's defintely not closed
maybe?
fyi {0, 1} isn't really a group
uh oh
you need to define the operation ;-;
it could be addition, multiplication, anything...
i just got into discrete srry
we can't really figure out what u mean
same i started grp theory like a week and a half ago
...
it's not the same
its logic
yes its logic
ok
groups in logic
it's just xor
so for set A ={1,0} is {A, ⨁} a abelian group
yes i think so
it is
what have you done so far
give me a sec breh
we need it to be closed
which it is because its always either gonna be 1 or 0
associative
which idk how to prove but maybe if i do truth tables for theta ⨁ phi and then phi ⨁ theta and they equal thats enough proofg
identity i really dont know how to do
inverse i really really dont how to do
i think i would just write out the multiplication table if i were you
yeah truth table
yeh done that
show
@silent sinew Has your question been resolved?
srry am back
one sec for phi ⨁ theta trusth table
phi ⨁ theta is same truth table
so it is commutative
composition table is wrong
is diagonal
but anyway
what is the identity element
@ancient helm come back 😢
,rotate
please fix the tables on the right but yes
you tell me
there's only two options, true or false
yeh
identity means that for any element in the group
if it undergoes the operation then it stays the same
oh it’s 0
just by looking at the truth tables
if it undergoes the operation then it stays the same
if it undergoes the operation with the identity then it stays the same
yes identity is 0