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according to gooji divisibility rules are not needed tho
The way they’re describing is also just using divisibility rules
But sure trial and error kinda works
What you really need is $4\ |\ A2$, or equivalently $4\ |\ (10A+2)$
kheerii
Find out all possible values of A from here and see which divide 63
the commonly stated divisibility rule for 4 is literally just "try it with 2 digits" because everyone that is learning about divisibility knows how to do that
I'll stop
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How do I know that theta is less than π/2
@neon iron Has your question been resolved?
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I wasn't sure where to ask this question, so I asked it here just to be safe.
Hi, I'd like to be able to explain the way to prove Lemma 1.7 (that for all n, n x 10 = n0) in a way that is educationally sound and easy to implement.
I have tried to prove it myself, but I'm not sure how to word the proof such that it is accessible to adults studying functional skills maths.
The notation n0 is kinda confusing imo
Oh really? Let's say n = 7, then that number would be 70. That's kind of what I mean. I hope that clarifies things.
Yeah well is this clarified somewhere? Because this can interpreted as multiplication by 0
But uh maybe that’s not so weird since you described this was for a certain public of people(?)
People studying Functional Skills Maths.
The reason this lemma exists, is so I can show that multiplying by 100 (which is necessary for converting pounds into pence) is about adding two 0's to the right of the number.
Why not explain it in terms of the number base system? This is more or less a feature of base 10
The number base system... That could work, but I want to make sure that the proof 'answers the question', as it were.
Instead of relying on an induction proof which seems a lot more challenging to explain
I mean, proof is hard. I'll drop the induction proof with immediate effect. After all, base 10 might be a better proof for functional skills students.
Obviously if they have past experience and are comfortable with such proofs I can see it as maybe useful but when it’s more or less just to describe a feature of base 10 it seems sort of overkill unless I’m missing something
I mean, this is important for understanding how to convert £4.56 (for example) into pence only. And I'm going to tell you why.
As you know, £1 is equal to 100 pennies, so you've got to do 4 x 100 (which is 400), then add the 56 that is left over.
Yeah so if the importance here is understanding why this works and they haven’t had past experience with say Induction proofs I’m pretty skeptical you’ll achieve anything other than confusion
I mean, it's a lemma (as opposed to a definition), and the lemma needs proving, but I could always go ahead without a proof, since most people already know that multiplying by 10 involves adding a 0 to the right of the number.
Okay, if you’re adamant about this I won’t try and discuss that part of it.
So going back to the proof, in the second step, I.e the inductive hypothesis, you’ve included that inside the induction step, I think you should separate that, as they are different steps
I mean, okay. How can I argue with that?
When you say associativity, what do you mean by that exactly? It seems you’ve confused it with the distributive law
Let's change k+1 to a+b.
Then (a+b) x 10 = (a x 10) + (b x 10).
That's what associativity means, at least in this case.
Yeah this is not associativity I’m afraid
OK then. I concede.
Associativity is in respect to one operator and not multiple, and it’s when the order in which you can calculate say a + b + c doesn’t matter
,w distributive law
Is it this what you meant?
Ok alright, also since they aren’t familiar with an induction step (or so I assume) I think it would help if you conclude that this holds for all natural numbers n due to the induction principle or axiom, in order to make the conclusion you wanted to
That is, at least make reference to what is actually allowing you to do this conclusion
I think you were right the first time... but I'll see if I can reference what is causing me to make the conclusion that "Multiplying a number by 10 is equivalent to adding a 0 to the right of the number."
Oh and yeah specify this proof holds for natural numbers
Sounds good
I've changed it to "Multiplying a whole number by 10 is equivalent to adding a 0 to the right of the number."
I suppose since my target audience knows only basic stuff, I'll forget about the proofs for now.
Thanks for helping me to decide that.
No problem! I think it’s cool that you’re at least trying to include that more rigorous taste of math
Instead of leaving things to be true “just because they are”
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Hey
I don't know the formal definition of continuity cause the teacher was taking too long to explain it
but basically what I gathered was
I mean they said that you should be able to draw a function without lifting your pen but that is not very mathematical lol
So formally
If a function is said to be continuous around a point x if LHL(x) = RHL(x) = F(x)?
This is what the definition should be right
is this correct?
This will only happen when the function has no breaks
Wait this does not cover the end points
assuming a function ends at a point then RHL may not exist, so LHL will not be equal RHL
well only the relevant limit at the endpoints has to equal F(x)
alright, so only one of the two limits?
and this definition then is not for endpoints?
yes
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any hints on (c) ? I literally have no clues about on one...Appreciate any helps
$I have x>1, x<1, and x^2<1, and x is not equal to 0, how is the answer -1<x<1?$
.....? Sry this is my channel
whats Gn and An?
so if you apply part (b) as they suggested, what do you get?
@strong sable Has your question been resolved?
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this
yeah sure, but replace "G_n" and "A_n" by their values here
like what is geometric mean of a_1,...,a_n,(A_n) 2^m -n times
and what is arithmetic mean of ...
yea that's the piont idk
I dont know how to write the GM and AM form of a_1,...,a_n,(A_n) 2^m -n times
I give this just as an example
a_1+...+a_k/k
what do the commas mean?
edited
keep a_1.... a_n as they are
and now I'm gonna define
a_(n+1) = A_n
a_(n+2) = A_n
and so on
until a_(2^m) = A_n
what's the arithmetic mean of a_1,....,a_(2^m)?
it's the arithmetic mean of a_1 up to a_n
it's NOT the arithmetic mean of a_1,...,a_n,A_n 2^m - n times
yea, why a_(n+1) = A_n ?
you want the arithmetic mean of this
as (b) said, when $k = 2^m$, you have $(a_1...,a_k)^{1/k} \leq \frac{a_1+...+a_k}{k}$
rafilou2003
Except
you don't have n = 2^m anymore
but you still want to use this result
so what do you do?
you add more terms to take the mean with
and be able to use (b)
that's the point of the hint
it tells you
use (b)
with a_1,...,a_n
and add to that A_n as many times as you need to reach a total of 2^m terms
so
a_(n+1) = A_n
etc
up to a_(2^m) = A_n
now we have 2^m terms
i see
so AM of a_1,...,a_n,(A_n) 2^m -n times= (a_1+...+a_n+a_2^m)/2^m
GM of a_1,...,a_n,(A_n) 2^m -n times= \sqrt{a_1......a_2^m}
(a_1+...+a_n+a_2^m)/2^m>=\sqrt{a_1......a_2^m}
@strong sable Has your question been resolved?
@opal vault does this correct?
@strong sable Has your question been resolved?
yeah that's it I think
it's missing some ... sometimes
for example AM is (a_1+...+a_n+***...+***a_2^m)/2^m
aaah yes
then .... It's proven? Done?
?
we have proven that the geometric mean of a_1,....,a_2^m (call it G_2^m if you want) is smaller than the arithmetic mean of a_1,...,a_2^m (A_2^m)
but we wanted to prove that the geometric mean of a_1,....,a_n (Gn) is smaller than the arithmetic mean of a_1,...,a_n (An)
so no it's not done
write out what G_2^m and A_2^m are in terms of Gn and An
and manipulate the inequality G_(2^m) <= A_(2^m)
to hopefully get G_n <= A_n
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how do you find the range here?
i'm super confused
hint: what is (x + 1/x)^2
the expanded form is x^2 + 1/x^2 + 2 though no?
nope
that problem is from your average algebra book, do you need that kind of stuff?
i have never heard of amgm inequality
no you dont
i don't see how can you continue this
i have tried multiplying x^2 by both sides but it didn't really take me anywhere
We have to find y which has a preimage ,you can solve this equation by quadratic formula and find the value of x^2 in terms of y
Then possible values of y is range
i'll try applying the quadratic formula
you apply it like this right?
No coffecint of x^2 is y not 1 and quadratic formula equal to x^2
This is quadratic equation in x^2 not x
is there a reason behind setting x to x^2?
Because this is quadratic in x^2 you can write x^4 (x^2)^2
Which give value of x^2
oh i see
so this is correct right?
i never had a case where you'd have to use a quadratic in order to find range
There is -1 in front of root
[2,…infinity)
Oh sorry yes
yea, i'm aware but can't tell how to get to the answer
AM-GM
There is -y in front of root
is there no avoiding this?
-b+√b^2-4ac
i don't think AM-GM is ever used in hs
make a perfect square
it is
oh wow
it can?
(x-1/x)^2 = x^2 +1/x^2 -2
this doesn't equal to this expression right
simolify it
alright i think i'll resort to using something like AM GM
You can see possible values of y is -2<=y<=2 which is range
why?
i literally told you x^2 + 1/x^2 = (x-1/x)^2 +2
and (x-1/x)^2 >=0
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So I am trying to find the asymptotic runtime of an algorithm. I am kinda stuck on the last step. I found the formula for total number of operations which is
$T(n) = \sum_{i=1}^{n} \frac{(n-i+1)(n-i+2)}{2}$
Now I am not sure what to do next
Calc III Victim
Write T(n) in closed form, then use master theorem
Or is T(n) your total runtime and putting it in closed form is where you are struggling?
right
acc give me a minute im going to try something again rq
wait a minute so I when I expand this I get
$\frac{1}{2} \sum_{i=1}^{n} (n^2 - 2ni + 3n + 1 - 3i)$
and $\sum_{i=1}^{n} n^2 = n \cdot n^3$ right so could I ignore eveyrhting else since surely this would be the dominant term
Calc III Victim
The 2ni sum would also be O(n^3) btw
actually, it might even cancel out the n^3 terms leaving you with O(n^2)
how
2n * (n(n+1))/2 = n^2(n+1) = n^3 + n^2
oh ur right
so n^3 - n^3 + n^2
n^3 - n^3 + n^2 + 3n^2 + n + (3n^2 + 3n)/2
5n^2 + n + (3n^2 + 3n)/2 = (13n^2 + 5n)/2
multiplied with 1/2 outside we get (13n^2 + 5n)/4
so the dominant term would be 13n^2/4 so its O(n^2) ?
@rigid ivy is this correct?
nah I got something different
not sure how you got this
Okay, first, what is $\sum n^2$?
SWR
alr so this is how I got it
n^2 = n^3
2ni = 2n * (n(n+1))/2
3n = 3n^2
1 = n
3i = 3(n(n+1))/2
wait shit
my dumbass
added the last one
smh
it should have been
n^3 - n^3 + n^2 + 3n^2 + n - (3n^2 + 3n)/2
= (n(n-1))/2
right
so (n^2 - n)/2. O(n^2)
Where's the i² term?
There's an i term in both expressions, so their product should have an i² term, should it not?
oh tbh with you I put it in a calculator so it could simplify it for me faster and I got that
let me try again
it probably did i²=-1
oh LMAOOO IT DID
fuck
alr so it should have been
n^2 - 2ni + i^2 + 3n - 3i + 2
right
$T(n) = \sum_{i=1}^{n} \frac{n^2 - 2ni + i^2 + 3n - 3i + 2}{2}$
Calc III Victim
there
alr lemme try this rq brb
n^2 = n^3
2ni = 2n * (n(n+1))/2
i^2 = (n(n+1)(2n+1))/6
3n = 3n^2
3i = 3(n(n+1))/2
2 = n
so it would be
n^3 - (n^3 + n^2) + (n(n+1)(2n+1))/6 + 3n^2 - 3(n(n+1))/2 + n
(n^3 + 3n^2 - n)/n
so O(n^3)?
@rigid ivy
yes
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can someone plz help
How far have you gotten so far?
While I type this wdym decomposition- I believe I know by a different name but just making sure before I go on a tangent lol
Okay what I thought just wanted to be sure lmao
Yup
Alright, so we have
126x - 3x^2 - 3x^3
And we know it's factors are
-3x(x - A)(x + B)
A and B being unknown values
Remember, factors can divide into their larger numbers perfectly- does knowing this help any?
Lol that's fine, the main thing you need to notice to break this down is that we have a known factor of -3x, meaning we can divide that polynomial by -3x, which in this case will turn it into a quadratic that's much easier to decompose
After that it should just be your normal decomposing, you just had to do extra steps to get there
Yes I already did that and right now I have -3x(-x^2 - x + 42
But I don't know what to do after this
Remember to change sign when you divide negatives :p
And after this you can kind of ignore 3x and start finding your (x - A)(x + B)
Whats your first step in decomposing this?
Is it possible you could tell me what the answer is and I could try reverse engineering it
I could if you want to but I think that would take away some potential decomposing experience, also you only really got like 2 major steps left lol but since we're this close up to you
I think I'll take the answer and worky way through it because I just need to understand the decomposing and I think I will be able to reverse engineer from there so I'll take the answer please
(x - 6) should be your final answer
Thanks and ur sure righr
If it helps any cause idk if you could reverse engineer this lol
Your first step in decomposing should be to find 2 numbers that multiply to a*c, and also add to b
@stray wave Has your question been resolved?
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<@&286206848099549185>
Hi you need help?
@burnt swift Has your question been resolved?
@burnt swift Has your question been resolved?
Have you factorized 32767?
,w factors 32767
Alr, so a is completed
whats up
with what
can you send it again
you have to simplify the expression then separate the compound inequality into two inequalites
we need to use little fernat theorem most probably
yeah
I'm trying to
To find an integer ( x ) such that ( 1 < x < 2 \times 32767 - 1 ) and ( 2 \times 32767 - 1 ) is divisible by ( x ), let’s break it down:
Calculate ( 2 \times 32767 - 1 ): [ 2 \times 32767 - 1 = 65534 - 1 = 65533 ]
We need to find an integer ( x ) such that ( 1 < x < 65533 ) and ( 65533 ) is divisible by ( x ).
The factors of 65533 are the integers that divide 65533 without leaving a remainder.
To find such an ( x ), we can start by checking the prime factorization of 65533. However, for simplicity, one of the factors of 65533 is 65533 itself, which is the largest possible ( x ) in this range.
So, one possible answer is ( x = 65533 ).
That should help a little more
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hello
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✅
I think its A
Okay give me one minute so I can write all down to help you understand
Let’s break down the problem step by step:
Define Variables:
Let ( p ) be the cost of one pencil.
Let ( s ) be the cost of one sharpener.
Let ( x ) be the number of pencils Elsa bought.
Let ( y ) be the number of sharpeners Elsa bought.
Relationships:
The cost of one sharpener is $2 more than the cost of one pencil: ( s = p + 2 ).
Anna bought twice as many pencils and 10 fewer sharpeners than Elsa:
Anna’s pencils: ( 2x )
Anna’s sharpeners: ( y - 10 )
Total Cost:
Elsa’s total cost: ( xp + ys )
Anna’s total cost: ( 2xp + (y - 10)s )
Equal Spending:
Since Elsa and Anna spent the same amount of money: [ xp + ys = 2xp + (y - 10)s ]
Simplify the Equation: [ xp + ys = 2xp + ys - 10s ] [ xp = 10s ] [ x = \frac{10s}{p} ]
Substitute ( s = p + 2 ): [ x = \frac{10(p + 2)}{p} ] [ x = 10 + \frac{20}{p} ]
Minimum Integer Value:
For ( x ) to be an integer, ( \frac{20}{p} ) must be an integer.
Therefore, ( p ) must be a divisor of 20. The divisors of 20 are 1, 2, 4, 5, 10, and 20.
Calculate ( x ) for each divisor:
If ( p = 1 ), ( x = 10 + 20 = 30 )
If ( p = 2 ), ( x = 10 + 10 = 20 )
If ( p = 4 ), ( x = 10 + 5 = 15 )
If ( p = 5 ), ( x = 10 + 4 = 14 )
If ( p = 10 ), ( x = 10 + 2 = 12 )
If ( p = 20 ), ( x = 10 + 1 = 11 )
Minimum ( x ):
The minimum value of ( x ) is 11 when ( p = 20 ).
Total Pencils:
Elsa bought ( x = 11 ) pencils.
Anna bought ( 2x = 22 ) pencils.
Total pencils: ( 11 + 22 = 33 ).
So, the minimum possible number of pencils bought by Elsa and Anna together is 33.
That should help
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for 9b the solution says 3y - x = 0
I don't understand though
Because what I did was set the deravative equal to 0
you can't divide by 0 too
so I have no idea how 3y - x = 0
Using derivarives to find this point isnt neccessaey, but notice that 3y-x = 0 doesnt set derivative to 0 it kinda sets it to infinity, which makes sense if you look a the picture. The tangent line at point P is vertical and derivative define its slope, so it makes sense that derivative is equal to +- infinity.
Its hard to explain with words, but imagine that the tangent line is rotatin counter clockwise, which you interpret as the derivative having a bigger value, it can never be completly vertical, but it will get close. So in infinity it will be vertical
so can I say the denominator of the deravative will always equate to 0 in questions like these
cause it tends to inifity
infinity
ohh wait that tangent line
is an asymptope
isnt it
thats why theres the infinity thing
But for me its pretty intuitive, if derivative is 0 then the tangent is horizontal, a vertical tangent means that the function grows infinitely fast
not exaxtly but thats how i explain this to my self
It just goes completely vertical, but basically yeah
Im not sure how asymptotes work for multivadiable functions, but in single variable limit must be +-inf
here the limit is P which is not inifinity
I think I'll just go with this
until I'm proven otherwise
hahaha sure
thanks lol
With some practice you will gain some intuitiom on how infinity and stuff like this works.
yeah
Its confusing at first
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What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
for the second integral
set e^-3x dx to dv
and u = 2x
then solve
$C-\int 2xe^{-3x} \dd x \to \int \underbrace{2x}{\text{\scriptsize{u}}} \underbrace{e^{-3x} \dd x}{\text{\scriptsize{\dd v}}}$
what method is this
IBP
??
ren
$C-\int 2xe^{-3x} \dd x \to \int \underbrace{2x}_{\text{\scriptsize{u}}} \underbrace{e^{-3x} \dd x}_{\text{\scriptsize{\dd v}}}$
```Compilation error:```! LaTeX Error: \mathrm allowed only in math mode.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.1421 ...^{-3x} \dd x}_{\text{\scriptsize{\dd v}}
}$
You're in trouble here. Try typing <return> to proceed.
If that doesn't work, type X <return> to quit.```
integration by parts
i... think that's the most optimal method here?
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smart
to get x^2 +2xy + y^2 = 36 + 2xy
then (x+y)^2 =49
so x+y = +- 7
I've got these solutions so far using x+y = 7
wait why
But when i sub into x+y = -7 i get the wrong answer
why what?
you found x + y by adding 2xy
subtract 2xy and find x - y
you'll have linear equations
oh wait same thing nvm
any idea why this is?
these solutions are correct
did you plug it back in and check if they satisfy
sometimes you do get extraneous solutions
but since xy = k has two branches you should have 2 sets of solutions
each set with two values for x and two values for y
@hollow rose Has your question been resolved?
i only plugged it into x + y = +- 7 because this is supposed to be a non-calc question
it's fine it's doable without a calculator
u can do it this way
the factors of that equation are x²-14x+13 and x²+14x+13
u can find the x solutions
and then substitute it to get y
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Anyone know how to solve this (x^2) ln(x^2))=2ln(2)?
do uk any log properties
Can you do anything with that?
Yes
You can deduce from here and prove with properties of log if u want that A = B
In your case, A = x^2 and B = 2
really? how
If I say Aln(A) = Bln(B), using log properties you can say ln(A^A) = ln(B^B)
From here, do the inverse function.
e^(ln(A^A)) = e^(ln(B^B))
A^A = B^B
A=B
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this doesn't necessarily imply A^A=B^B though
the function f(x)=x^x is not a bijection
you can only conclude that here because B>1, and for x>1 f(x) is indeed a bijection
it's an important conclusion
Yes, i am using the context of the exercise
well, if you had $x^x=(0.8)^{(0.8)}$ then there would be two distinct solutions and not one
kheerii
Then you cant do that?
✅
Why
the function f(x)=x^x is bijective if x>=1
but if x<1 you can have two different values
Because we hare working with ln2
I mean that
$(x^2)^{(x^2)}=2^2$
kheerii
But How can you Realise that function has more solutions If its smaller than 1 with out graphing
What If you don’t know?
well, you can differentiate the function to check
And why negative values are not aceptable?
negative values aren't in the domain of x^x
well technically you can say negative integral points are
but they give us negative values anyway so it doesn't matter
not necessarily
..?
Okay thanks then is this the only way to do it or are there any other ways to solve that equation?
there's $(-2)^{-2}=0.25$
nameless individual
but that's still less than 1
no that method is correct
$\left(-\frac23\right)^{-\frac23}$
nameless individual
I was just pointing out that saying x^2=2 does not necessarily give you all the solutions
you should just force $x>0$
nameless individual
kheerii
welp
but still
yeah we usually do do that
I didnt say it wasnt corect i just asked If there are any more ways to do it or is this the only way
it's implied here because it's (x^2)^(x^2)
only if you choose the principal value conventionally
i mean, this is the easiest
and probably the only reasonable method
there's no "only way"
you can always go on a shopping spree before you solve the problem
I have read that before 🥔
from me? or where
Yes , from u lol
How can you do that?
If you differentiate you get xx^(x-1) right? And that sounds pretty useless
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Hey Guys
How do I find the derivative of i(x)=17 * x^2 * ln(32x) ?
$f(x)=17x\ln{(32x)}$
sealpup321
sorry just to make it easier for me to read
ok so use the product rule with $u=17x$ and $v=ln(32x)$
sealpup321
to differentiate $v=ln(32x)$ use the fact that $ln(x) = \frac{1}{x}$
sealpup321
I tried to use a calcultor for this part, it says 1/x
to differentiate $v=\text{ln}(32x)$ use the fact that $\frac{\text{d ln}(x)}{\text{dx}} = \frac{1}{x}$
Your LaTeX Helper
How do I use the product rule for this??
its the chain rule, then the product rule
Is the chain rule for the ln(32x) ?
yes
For the ln(32x) with the chain rule, I got it to be 1/x
How do I use the product rule for the rest?
this is wrong
the formula you want to use for chain rule is $u^{\prime} f(u)$
sealpup321
sorry I dissapeared earlier had dinner
how? (haven't really seen this)
have you learnt chain rule?
not much of it
sealpup321
anyway use this and tell me the answer
Math explained in easy language, plus puzzles, games, quizzes, worksheets and a forum. For K-12 kids, teachers and parents.
The product rule tells us the derivative of two functions f and g that are multiplied together ... (fg) = fg gf ... (The little mark means derivative of.)
@inland minnow you good?
I actually don't quite understand how to use the rule you sent me
thats fine lets take it a little slower then
worst thing you can do is get stuck and start to slow down or procrastinate
ok... wanna vc?
fingers are tired from typing
wait never mind I thought there were vc calls in this server
are you still there @inland minnow
yes
coolio
so you will want to use the chain rule when you have something trapped in a function
eg. $(x^2+4x+4)^5 \ cos(3x+2) \ ln(32x)$
sealpup321
these are all examples on when you would want to use chain rule
basically if something is trapped in brackets you probably want to use chain rule
Every calculator I have used gives me ln(32x) as 1/x (for the derivative)
when you do this you have to recognise whats in the brackets as u and whats outside and f(u)
cool and?
as I was saying
tell me what these are in regards to ln(32x)
awww piss you got it here
I missread sorry about that
anyway you dont seem confident work me through what you did and then I'll help you with product rule
it's okay, I may have learned something new from that also
phew 🙂
The only thing I have done until now is that I tried differentiating 17 and ln(32x), whereas I got 1/x to be the derivative for ln(32x) and differentiating 17, I got 0
$17x^2$ not 17
sealpup321
but what I want you to tell me is how you used the chain rule I want to make sure you aren't just using an online calculator
Ohh, that's one thing I was stuck on
do you have the answer?
not yet
I don't know if it's correct
ok I am a little confused?
first whats g(x) and f(x)?
instead of writing stuff down I have to go soon so just message here
sealpup321
yes, that's what I was trying to do
sealpup321
yes
ok so using the formula $u^{\prime}f^{\prime}(u)$
sealpup321
sealpup321
I’m here, just needed To tell you I work with this table
ok thats an awful table but not important
wow
no nevermind I hate that table
it doesn't explain anything and just gives you a ton of rules
and it got sin(x) wrong
alright to differentiate 32x
yeah, i know i fixed it to -sin
no i mean if you differentiate sin you get cos not -cos
it got them the wrong way round
.
It's 32
sealpup321
its on this sheet
ln(32) would be 1/32, right?
just tell me what you get if you differentiate ln(u)
1/u
sealpup321
so multiply 32 and 1/u to get $u^{\prime}f^{\prime}(u)$
sealpup321
do you have the answer?
32/u
yup
now you want it with x not u
so replace u what its equal to
what do you get?
and that's 1/x
2x
34x
good
cool so we now have the four parts we need to differentiate using the product rule
$u = ln(32x) \ u^{\prime} = \frac{1}{x} \ v = 17x^2 \ v^{\prime} = 32x$
sealpup321
I wan't say yes, but not quite sure (mostly yes)
ok thats good
I am giving them names in a way
u is the abbreviated form of ln(32x)
and the $^\prime$ just means I have differentiated it
sealpup321
Can I use this?
the product rule is $vu^{\prime} + uv^{\prime}$
sealpup321
sorry
yes its the exact same
just instead of g(x) and h(x) i have use u and v
but they mean the same
thats the product rule
alright ill give you a minute
$g(x) = ln(32x) \ g^{\prime}(x) = \frac{1}{x} \h(x) = 17x^2 \ h^{\prime}(x) = 32x$
sealpup321
oh yea
but otherwise well done!
you did it
by the way this is quite advanced math to be doing (I imagine you are in the german equivalent of gcse) are you in a gesamtshule?
oder gymnasium?
lol, no I am in a danish high school in my first year (we are supposed to do this on our second year)
fair enough
anyway that sheet makes things way more complex then it needs to be
I would recommend looking into differentiating in your own time using youtube or something
as that sheet could easily cause a ton of misunderstandings
anyway goodnight
good night
Thank you very much for your time, I really appreciate it
no worries and goodluck o7
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can i get the b in the y=mx+b without having the y or the x ?
without more context your question doesn't make too much sense
can you get b given points? a graph? an equation?
b the the intersection of the graph with the y axis
without y ig it would not be techincally possible
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I simplified this into vertex form as 4(x - 4)^2 + 9 is this correct?
if you try expanding 4(x-4)^2 + 9, you get something different from y
so that's not the correct vertex form
try factoring the 4 out and manipulate to get something that looks like a perfect square
y = 4(x^2 - 2x) + 5
if that was x^2 - 2x + 1 in the parentheses, you'd have a perfect square
Is it y(x-1)^2 - 11?
4(x-1)^2 - 11?
almost, double check the constant
that expands to 4x^2 - 8x + 4 - 11
and you want it to be 4x^2 - 8x + 5
so instead of -11, what should it be?
+1
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✅
Hold up neil, I am significantly confused right now
Could you work the problem out for me so I can see the process???
If anyone could work the problem process out for me that would be great
$4(x-1)^2+1=4(x^2-2x+1)+1=4x^2-8x+4+1=4x^2-8x+5$
Your LaTeX Helper
Do you need help on expanding $(x-1)^2$?
Your LaTeX Helper
@haughty ember
Oh, I don’t get how it works
As in the how to get the constant values
And how to establish the -1 value
Because usually when a = 1 you halve b value and add/subtract
The $-1$ value can be obtained by the formula $\frac b{2a}$.
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i couldnt get the last two lines like how did the no. of solns become nine...how did we get pi/24, pi/8 etc
read equation (ii) and equation(iii) and their conditions for n
look at your interval
it states the interval
like how to we know till what number we can include in the interval
like how many values of n can i assume and which one will be the last value of n in the interval
hey can any one help me tomorrow at 8:30 with some Hw it’s an online class pls i would do it but im out of time and my class finishes tm.
I know it is not my questions but can someone explain how we got the equation (i)
why do we not have pi/12?
its a formula for general solutions of trig eqns
it says if sin x= sin alpha
then x= npi+(-1)^n alpha
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Explain the distinguishing feature of the distance between the foci and a point on the ellipse.
does this explanation make sense?
is it accurate i mean
The distinguishing feature of the distance between the foci and a point on the ellipse is that the sum of the distances from the point to each focus remains constant for all points on the ellipse. This constant sum is equal to the major axis length of the ellipse.
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hi
In the figure above, tanB= 3/4. If side BC=15 and side DA=4, what is the length of DE?
@minor wharf 6
@minor wharf Has your question been resolved?
why
@minor wharf Has your question been resolved?
@minor wharf
.
but why multiplying BA with 4/5 to find DB and BA with 3/4 to find DE
and what is the value we are multiplying with 4/5 to find BA?
we find DB by subtracting the length of BA by 4, because length of DA is 4
We don't multiply BA by 3/4 to find DE, but we can multiply BD by 3/4 to find DE
Because we know there exists a ratio of 3:4:5 for the sides AC:AB:BC
so we can find the length of side AB (or BA) by multiplying BC by 4/5
does that answer your question?
hey
Nah
Where can I learn the full context from, what are the rules called?
Bro left the server
Anyway thnx for the help 😭😭?..
Btw why do people keep leaving this server, 😭 it's not the first time to see this happening
I think I get it now, but we don't even know BD to multiply it by 3/4 is what I'm telling you
Okay so that's to find BD?
Basically this (4/5)=(x/15) no ?
4x15= 60
60/5=12
So BD=12 ?
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need help with part c
!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
how did it travel 10 m?
shouldnt it be 5m there?
it went from 15 to 10m
in that ime period
time
I think you're right it should be 5
yh i think its a mistake
i think the rets of the answer is correct
rest
ye
thank u
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The line where $$ \alpha (\alpha - 1) ... (\alpha - n + 1) (1 +x)^{\alpha - n} = \alpha^{n} (1 + x)^{\alpha - n} $$ doesn't make sense to me
sed
why not
the entire line?
It's just generalising what you had above
plug in n=2,1,0 etc
do u see?
I get the generalisation but not the equality here
which equlaity?
the one i sent
that just seems like the factorization identity
Oh
I just realised
I think $a^{\underline n}$ is the falling factorial
normalAtmosphericPa=101,325
Thanks anyway, massively helped
but if it's from wikipedia, they generally do shitty notation like that
Proofwiki
yeah similar
But i mean for all the other brilliant proof they've done i still love it
❤️
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This is a very famous problem
Hi
I don't understand how
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BD is found by subtracting the BA by 4, because the length of DA is 4
so BD is 8
okay
I found BD is 12 because I used this equation: (4/5)=(x/15)
okay
yup you got it
dyk how?
You can multiply BD by 3/4 to get DE
this is because the inner angles of triangle BDE and BAC are the same, therefore the ratio for side lengths are also the same
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Hi
Determine parametric equations for the line through (-2, 3) and parallel to the line with vector equation Vector I = (−2, 1) + t(6, 4).
How can i do this
write the line in vector form, then just write the equations for x and y
Wait so I do tip - tail of (-2,3) and (-2,1)
The answer i get would be [x,y] = [tip-tail ans] + t[6,4]
Then i get the parametric form
Atleast tell me if i am right or wrong
Why should i care abt the slope all I need is the parametric equation
@acoustic pecan Come back
I need you too
it would be (-2,3)+t(6,4)
What abt the (-2,1)
its irrelevant
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How do I find their intersections by solving for either x or y? I have tried but I keep getting quartic equations and I don't know where to go from there
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
Find the area of the region bounded by x^2=y+1 and y^2+2x+1-x=0
yes i've seen the graph and im stuck at y(y^3+2y-1)=0
this really doesn't seem right to me..
You can solve depressed cubics like that
howww
Oml
maybe ask the person who assigned the question to you if the data in the question is wrong
This looks bad tho
any way you do it you have to solve a quartic or a cubic or something like that
or you could parametise both the parabolas and solve it that way maybe
that wouldnt be a clean solution though right?
if the numbers are nice then it could be
(x² -1)² + x + 1 = (x-1)²(x+1)² + (x+1) = (x+1)((x - 1)²(x+1) + 1) = 0
Does that look any easier
Solving (x-1)²(x+1) + 1
oohh but how will I go from there
,w expand (x-1)^2(x+1) + 1
,w factorise y^3 + 2y - 1
very nice




