#help-33
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Anyways my issue with it is that i would usually just figure out the equation corresponding to the graphs and then put those equal to eachother and solve for x. Issue is i cant analyse the a, b and c values in the parable (arch like one) so idk what to do
notice the unit squares
I have in fact been staring at those
Is that all? Theres no big calculation i gotta do?
i mean you can if you want but
it's just right there isn't it
given no information whatsoever, that's all you have and all you gotta use i guess
Omg okay thank u so much!!!
you're welcome 👍
Okay second issue
Ive done all this
And i dont realky get what a is? Like what does a and b determine and how do i know what a is?
Cus if a is the percentage with wich the grap declines its way too high
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.
Okay this is the original problem, translation will follow shortly
how did you get that number for b?
Basically it says: the data below show the development in childdeaths in bangladesh i the period 2000-2019. Child deaths are measured in number of deaths for kids under the age of 5 per thousend born living.
In a model the childdeatlyness f(x) can be described by a graph
f(x)=b•a^x
Where x is years after 2000
A. Choose(?) The numbers a and b by exponential regression on all the datas (i have a seperate document with more data)
I did the regreasion and it gave me f(x)=85,591•(o,946894)^x
oh I see. it wants you to do a regression
what doesn't?
I dont really get what a and b determines in the graph and if either of them is the decline of the graph then how are they positive numbers?
b is the y-intercept
i.e., the number at time 0
it's been a long time since I did this kind of regression, but I think that the rate of decline is actually ln(a)
,calc log(.946894)
Result:
-0.054568124479122
so that would be a 5% decrease
Ooooh okay that makes a lot more sence
I have learned about log and ln so i get it nit thank you!!!
*now
yw
But then can i just put b=(0.946894)?
no, b is 85.591 or whatever
Sorry i meant a
Keep mixing them
Imma do it
A=(0.946894)
I got a thrid and final question tho two sec
This is the assignment
It says: a quadratic polynomial f is given by
f(x)=2x^2+8x+k
A. Find the two zero points for f, when k=-4,5 (which i did)
B. Find k, so that f has exactly one zero point
(Zero point is where f(x)=0)
I dont really know how im supposed to do assignemnt b
do you know the delta
and its properties
ax²+bx+c=0
🔺 =b²-4ac
i'm pretty sure you've heard it
I do not
Only in relation to physics
No actually i do know it
Sorry we just call it d, or the discriminant
that's the same thing yeah
so there's few things you gotta know
like when d>0, there's 2 real roots to that function (meaning it intersects the x axis at 2 different points)
and when d<0, the function doesn't intersect the x axis at all, leaving you with no real roots
can you guess what would happen at d=0
1 intersection 😎
👍👍
How is this used i correlation with my issue tho?
you can rewrite d=b²-4ac as d=(8)²-(4)(2)(k)
and set that to 0 👀
How can i set that to 0 tho? Like how is that possible?
Wait it makes sence
Sense
Thank you so much! This has all ben such a great help!
you're welcome
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isnt this there are an infinte amount of solutions
4c + 6m = 100
8c + 12m = 200
first equation you manipulate it
but its gonna be
8c + 12m = 200
8c + 12m = 200
so what is the answer
ok
but that option isnt there lol
khan academy sucks
because you just told me the answer is
there is an infinite amount of solution
which is not the same thing as there is not enough information to determine the exact number of capulets and montagues
help please
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hi
i need help solving this systems of equation
the two equations are
f + p = 21
4f = p + 24
could i divide the bottom equation by 4 to solve for f?
that works, there are many ways to do it, as long as you can find an equation solely depending on one of f or p, and solve them individually, it's fine
substitution would be easiest here, probably
Hi
I need help
How can I substitute
I am not allowed to to substitute cause f is not the same as 4f
right, it isn't
So how
I solve for f?
But that's what I did
Ok here is what I am trying to do
I'm trying to isolate f so I can use whatever f is and substitute it into the first equation
And I need help with fractions
I understand. I'm saying it's easier to solve for f from the first equation, and use that in the second
So the picture I sent in asking if I did it right
Oh
So f would be f = 21 - o
f = 21 - p?
yup
very much so
Ok so how do I know which order is correct
you have f + p = 21, right?
Yes
and you subtract p from both sides
Yes
which gives you f + p - p = 21 - p
Oh so it's 21 - p
yup
do you understand how to use that expression for "f" in the second equation?
Ho Ho Ho
Y'all are so smart
Yes I know how to do systems of equations
I guess I was just being blind
Anyways I got the answer right
no worries
P is 12 and f is 9
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Help pls
<@&286206848099549185>
well you know the area is $\pi {r_2}^2 - \pi {r_1}^2$
Potatomonke
where r_2 is the outer radius
and r1 is the inner radius
so $\pi {r_2}^2 - \pi {r_1}^2 = 10 \pi$
Potatomonke
Potatomonke
we are trying to find the width, which is r_2 - r_1
is {r_2}^2 - {r_1}^2 = 10?
we can factor this to get $(r_2 + r_1)(r_2 - r_1) = 10$
Potatomonke
Potatomonke
np
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Did I do smth wrong? How can I proceed?
(to make it easier to read)
Thx
U see smth wrong?
i'm not sure i understand the question. could you try to explain it to me, or provide me some more context, or perhaps a picture of a prompt or something?
Find z
With z=x+iy
<@&286206848099549185>
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In a game of chance, six cards numbered 1 to 6 are lying face down on a table. Two cards are selected without replacement and the sum of both numbers is noted. State the total number of outcomes.
well which values are possible to be presented as a sum of two values between 1 and 6?
clearly the minimum is 3
and the maximum is 11
is it possible to achieve every value in the range {3,...,11}?
@ruby cloak
yes. all possible
yop, then you know the total number of outcomes 🦇
sorry -- don't understand
well we know that 3 is the minimum outcome
11 is the maximum outcome
and all values between 3 and 11 are also possible outcomes
thereby we know 3 to 11 are the only possible outcomes
meaning there are 11-2 = 9 possible outcomes
3,4,5,6,7,8,9,10,11
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How would i do q13
everything right except it's 10a*a :)
and after that just remember that a*a = |a|²
Oops...
b*b = |b|²
and "a is parallel to b"
so let's remember what the dot product means
we project a onto b and then multiply the lengths
but if a is parallel to b
then a projected is just a again
Is magnitude squared just the original value
wdym
So magnitude 6 squared is just 6?
|a|² = 6² = 36
Ohhh u rite

OOPS.
:D
nw
therefore since a and b are parallel: a * b = |a| * |b|
because a_projected = a
I don't have the dot symbol here, but these are two different multiplications just to have it clear
left is vector dot product
right is normal multiplication
so written in latex:
but I wrote it here
as they're parallel
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I'm kind of lost of what to do at this point, using partial fractions
set that equal to the original function
$x^2(.....)+x*(.....)+....$ you could try doing something like this
BobTheBuilder
you can find the value of A and c by substituting x equals 0 and -1
now u compare coefficients in LHS and RHS
🤨
after having done this you should create the system with 3 equations, placing the corresponding known value to each
i have no idea what that means
What did you not understand?
literally everything, i don't know that x^2(...)+x*(...) is
okay
i basically don't know how i handle 5-x
all the examples we did had a x^2 if there was a x^2 in the Ax^2 place
oh so Ax^2+Bx^2, since there's no x^2 in the 5-x numerator is 0?
we didn't do any examples like that so i'm flabbergasted
yes the coefficient on the x^2 term must be 0
yup you can resubstitute into this and solve the integral
that gives me that, right?
be careful with the last integral
ah u sub
it's saying this is wrong???
without and without the bars
god i hate this software so much
don't need () when you have | |
it's the software being a dumbass, i needed to use their specific bars
I couldn't type in my own
the class made us pay $130 for this software and it doesn't even work
love it so much
that is upsetting it seems to be correct
@pseudo aspen Has your question been resolved?
subbing in -1 for A, you can setup B in terms of C or vice versa
so I do -1 + B + C = 0 giving me B = 1 - C?
yes
giving me C = 2
then i just use -1 + B + 2 = 0
and B = -1
got it, that makes sense
simple algebra that i forgot lol
this whole process seems like it's more algebra based than calculus ngl
if you did the previous calculations correctly everything is correct for now
yeah, got it right!
for this problem, i would need to use the division stuff?
in my notes i have something like this
but if you do the calculations you see that the numerator has a lower degree than the denominator, so no
You do the division only if the numerator has a degree greater than or equal to that of the denominator
ahh, i see
@pseudo aspen Has your question been resolved?
just going to keep this open for a little bit longer
if i see no help channels available, i'll close it though
.solved
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I don’t really understand what’s going on here
great for you
???
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this quite literally the first thing written in #info
why are you minimodding for no reason
whatever i give up
dont know why youre making such a big fuss if youve been in the server long enough youd see that this isnt unusual
So as you may or may not know, the photo current originally (before applying a potential difference to stop it) was because of the electrons that were ejected from the metal surface.
right
The fastest of those electrons had kinetic energy that you find out using the equation hυ = Φ + KE
hu
It's not u?
hf
υ
$\nu$
! What the hell am I doing here?
in my book frequency is denoted as f
Fair enough.
Yes, it normally would have.
But those electrons are now stopped because of the potential applied.
this is the voltage source im guessing?
Yes.
So as it turns out, to stop those electrons the potential applied has to be equal to the kinetic energy these electrons would have normally had because of the light source.
That's the idea.
by potential applied are u talking about like the voltage?
Sure, that.
so if the voltage is stopping the photoelectrons from running through the wire, how does it reach the collector?
It'd have reached the collector had there been no voltage.
And the voltage applied only acts after the electrons reach the collector.
They'd have had kinetic energy still but this voltage now acts against the electrons' motion.
is this the direction in which this is happening?
so it goes to the collector first?
this is more like it didnt mean to add the extra red line
or is it the other way around
Other way, conventional current (+ to-) opposes electron flow. Increasing voltage makes more electrons "build up at the collector" meaning the photoelectrons don't want to be there more
O
so if in the question it says "all emitted photoelectrons are gathered by a collector" if the voltage is stopping the photoelectrons from flowing in the wire, how does the collector ever gather it?
At the start of the experiment the voltage is low enough that all photoelectrons that want to get to the collector, do so
As you increase the voltage less and less reach the collector until none do
ohhh
Im confused why increasing voltage would reduce the current detected? I thought it would do the opposite no? from V=IR voltage is directly proportional to current
Yo you need help here still? I think I get it
yeap
Mk what do you want me to explain?
this
The voltage is essentially travelling in the other way to the photoelectron current
oh
This lowers the current of the photoelectrons emitted; as the collector becomes more "negative" the photoelectrons don't want to travel there as much, they're being resisted (repelled)
ahh okay
so this reduces the kinetic energy of photoelectrons and makes it move through the wire more slowly?
Yeah, so the voltage is known as the stopping voltage, and is the voltage that resists the photoelectrons
ohhhhhh alright that makes sense
It reduces it to make it not reach the collector
Only the electrons that have enough KE can bypass this to reach the collector
so thats why less current is picked up on the ammeter?
i see
Yep, less photoelectrons have the KE required to overcome the input voltage (stopping voltage) so it is less
I'll admit I have no idea if the stopping voltage is a current, I dont think it is
wait so the negative side of the voltage source is connected to the collector or something, is that why the voltage is fighting against the photo current?
Dude get lost
I'm still trying to find sources for this, I don't think this is right
The stopping voltage makes the collector more negative which increases the amount of KE required for a photoelectron to make it to the collector
I don't know how the voltage is applied...
Let me cook
alr lmao
I'm confused because if that symbol is a battery then wouldn't the stopping voltage induce a current on the ammeter?
I'm learning this topic rn btw
idk its just a voltage source im not sure if thats the same thing
Wait hang on its not closed, theres no current
Yeah batteries are a voltage source
the metal here acts as a current source
Nvm, I was thinking about the battery, I get it
Yes the negative side here makes the collector negative so that it creates an opposing electric force to oppose the photoelectrons
wait so im kind of confused, does the voltage source create electrons? or is it just a electrical force that guides the electrons
It's impossible to create electrons, it essentially gathers them
And having more electrons at a point makes that point more negative, which would be the collector in this case
so it just provides the force for electrons to flow in the circuit
?
ohh ok
i think i get it now
so if this was negative to positive, there would be no force the photocurrent has to fight against?
Hope that helps
If you want to mess around with the experiment I found this to be pretty good: https://javalab.org/en/photoelectric_effect_2_en/

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Oops, closed the other one
@open kayak Has your question been resolved?
@open kayak Has your question been resolved?
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not sure what answer do you want to get, it's like asking what's the difference between an orange and an apple
they are two distinct rules
sine rule
a/sin(A) = b/sin(B) = c/sin(C)
cosine rule
c^2 = a^2 + b^2 - 2*a*b*cos(C)
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if $y=x^2-3x$, then $\frac{dy}{dt}=\frac{dx}{dt}$ at x = ?
Joeller
$\frac{dy}{dt}=2x\frac{dx}{dt} - 3\frac{dx}{dt}$ = $\frac{dx}{dt}(2x-3)$
Joeller
and from this
$\frac{dy}{dt}=\frac{dx}{dt}(2x-3)$, then $\frac{dx}{dt}=\frac{(\frac{dy}{dt})}{2x-3}$ = $\frac{dy}{dt}\frac{1}{(2x-3)}$
Joeller
and since dy/dt=dx/dt so we'll just remove them so we'll end up with
$2x-3=\frac{1}{2x-3}$
Joeller
$4x^2-12x+9-1=0$ divide by 4, $x^2-3x+2$
Joeller
$x=1,x=2$
Joeller
dx/dt*
yea both satisfy actually
Yeah I thought so
its crazy that they have them both in the choices
I'll have to ask my teacher about this
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what role does n=2 play in this
if im finding convergence or divergence
No role, it could start at any index greater than -1
it shouldn't really make a difference, n = 1 produces a finite term so if this sum diverges then the sum would diverge even if n started at 1, and likewise if this converges then adding the n = 1 term will still lead to a finite sum
this sum coverges tho
yeah but it’s the same reasoning
ohhhhh ok
if the whole sum converges then starting one term earlier doesn’t make a difference 👍
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How do I solve b)
no clue i'm restarted
a) is 7
Average rate of change formula is $\frac{f(b) - f(a)}{b-a}$ when $a < x < b$
Potatomonke
$\frac{f(x-0.01)-f(x)}{0.01} = 7$
rynite
have you learned power rule yet?
nope
derivative based math is taught after functions based math
so what do I do now
derivative based math?
which part of the problem is this meant for
b)
in the book, one possible answer given is (4.5, 3)
idk how they got that tgho
tho*
im not sure if I understand
are you familiar with solving for the instantaneous rate of change at a point
yes
if you were to find a point **common ** to the instantaneous rate and the average rate , what could you do?
think in terms of x values
no idea, don't you need 2 points for average?
not one
think about the equations for each
Is this a cubic?
I think you'll likely need to solve the cubic and then check where df(x)/dx = 7
that is further on in functions , limits are taught before derivatives
because intermediate value theorem isn't enough here
But the question is asking for derivative clearly...
@twin ether try to set the equations for instantaneous and average equal to each other
like this
is f specified though?
average has already been found
we can find it with the graph if needed
well not necessarily....you're assuming its a cubic but it could be a crazier function
anyway considering its a cubic we can do it quickly enough
$\frac{f(x-0.01)-f(x)}{0.01} = \frac{f(5)-f(4)}{5-4}$
rynite
like that?
you can, but that's not how u're supposed to solve this
so anyway cubic is (x^2 -4)(x-2) = x^3 - 2x^2 -4x + 8
derivative is 3x^2 - 4x -4 which we want to be 7
3x^2 - 4x-11=0
just solve it
🤷♂️
im confused asf
no
no
so what has been taught in calculus?
im not taking calculus
which grade are u in
it’s advanced functions
a single chapter
yea
limits are taught first
hm I didn't
she gave you the def of limits
anyway ok
so let's do it slowly
assume the function is a cubic
what are it's roots
they're specificed?
from the graph
i found it
(x-4) x (x+4) x (x-2) right
yep
ok
so you're looking to find an x such that
[f(x+h) - f(x)]/h
with h being super tiny (we'll quantify)
so that this becomes 7
yeah I understand that
no he doesnt know derivatives
not sure how
no
oh
3x^2h + 3xh^2 + h^3 - 4x^2 - 4hx - 2h^2 - 8x - 4h + 16
what constant?
ok k
x^(3)-2x^(2)-4x+8 -(x+h)^(3)-2(x+h)^(2)-4(x+h)+8
is that what I should be solving
ah right
-(x+h)^3 - 2(x+h)^(2)-4(x+h)+8 - x^(3)-2x^(2)-4x+8
this right now?
oops
too many variables
the 8s still dont cancel out
you have to distribute. it's minus all of f(x)
ah
i forgot about that 😅
3x2h+3xh2+h3−4hx−2h2−4h
is that right
now
$3x^2h + 3xh^2 + h^3 - 4hx - 2h^2 - 4h$
clearer
no its not
rynite
no the variable h
ok
$h^2 + 3hx + 3x^2 - 2h - 4x - 4$
rynite
right?
why 0
oh ok
do i equal to 7
yea
yeah looks very close
I mean did we make a mistake
because while the roots look fine
-1.36 and 2.69 on the graph are decreasing points
I think we got the function wrong
is it because we didn't include the vertical shift/comp
yes, the function was wrong
its (x-4) * (x+4) * (x-2)
the zeros are -4, 2, 4
so (x^2 - 16) * (x-2)
oh
ight sec
do the same thing as before
good practice 🙂
you should get 3x^2 - 4x - 16 = 7
to be solved
@twin ether Has your question been resolved?
yeah sorry for late reply, I did something wrong
i got ur answer now
I have a question though, I don't understand why we didn't consider a in the equation, vertical shift/comp
whats a?
~0.26
im confused where are u getting -0.26 from?
can't be negativ
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How do I express this equation?
Hmm how
acc to you, what should be left after you take 3^p+2 common from the first term?
Factorise 3?
wdym factorise 3
Like take out 3 from the 3 terms?
1^1
no
Hmm I don’t get it 😭
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Is this correct
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can someone help me solve this
Try consider the general expression for each individual term
general expression ???
Well you know the binomial theorem right?
yep
$(x+y)^n = \sum^n_{k=0} {n \choose k} x^{n-k} y^{k}$
Afi
The general expression is ${8 \choose k} (\frac{x^3}{2})^{8-k} (\frac{a}{x})^{k}$
Afi
Since we are looking for the constant term, we want all the x to cancel out
And so we want to find k that satisfies
look at terms of the form $C^8_k x^{3k}/2^k a^{8(8-k)}/x^{8-k} = C^8_k x^{4k-8} a^{8(8-k)}/2^k$
n is 8
tyler
so k=2 is the valid term for the constant
this is the way my teacher did it but i want to know why x=1
so 8C2 x a^{8 x 6}/2^2 = 7 a^48 = 5103
so a^48 = 729
729 = 3^6
so a^48 = 3^6 => a^8 = 3
Its not that x=1
but x^(24-3r)/x^r is 1
a = 3^{1/8}
Since we are looking for the constant term here
There wouldn't be any x
why is it 1
Is 5x a constant?
If the term has x in it, then it is not a constant right?
tthe question is asking for the a and r vlue
e.g. 510, -0.888, e are all constants
5x, 99/x^5, x^2 are not constants
Looking back to your question
We know that the constant term is 5103 (which has no x)
Meaning that the expression for the constant term $\frac{x^{24-3r}}{x^r}$ must be a constant, i.e. 1
Afi
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How do I find the highest common factor of s to the power of 8 and s to the power of 6
it's easy in this case since s^6 divides s^8
its s to the power 6
it's just like trying to find the HCF of 2 and 8, well it's 2 because 2 divides 8
Would it be okay for you to break that down for me?
So I can understand how it divides etc?
yeah i can, if you're trying to find the HCF of 2 and 8, we know that 2 is a factor of 8 and also of 2, but also there are no bigger ones since 2=2, so nothing higher will be a factor of 2
similarly, S^6 is a factor of both S^6 and S^8, but if you try anything higher, it will no longer be a factor of S^6
How is S^6 a factor of s^8?
yep
Thanks! and how would I find the highest common factor of h^8 z^5 and h^7 z^6?
you would take the lower of the two powers in each and combine them. think "the max capacity for h's in h^8z^5 is 8" and for h^7z^6 it's 7, so we try to fill both with h's we can only fit 7 until one of them can't fit any more
and do the same for the z's
so how many z's go into each term?
Im sorry, I dont completely understand
that is okay, we should start at the basics actually, you are familiar with the term HCF? if not, we should start there.
yep
okay great
🙂
I havent done highest common factors of variables and exponents until today so def a learning curve 😂
Pretty sure ive got it nailed for variables now though 🙂
okay, that is fine. actually i want to start with an example for numbers, and it'll pretty much tell you how to do it for variables. I want to find the HCF of 18 and 24, how would you go about doing that?
i know this sounds simpler than what you want, but it's really instructive
Finding common multiples eg: 1,18 and 1,24 then working my way up till I find the highest one that goes into both
So in this one it would be 6
6x3 and 6x4
yes. okay, also do you know about prime factorizations (i promise i am getting somewhere with this)
Working on it, not completely there yet
okay, the point is that 24= (3)(2)^3 and 18 = (2)(3)^2
and we computed the hcf to be 6 = 2*3
so what i would do to find the hcf was to look at the minimum exponent of each of the primes (which in your case will be the variables) that divide it.
so we can go back to h^8z^5 and h^7z^6
i look and see "what is the minimum exponent of the h's" and i see that it's 7, and "what is the minimum exponent of the z's" and I see that it's 5
so we can just say that the hcf is h^7z^5
and in fact you can check for yourself that that's indeed the highest common factor
So the highest common factor is the minimum exponent of both variables in the equation?
yeah, you should verify my statement by trying to see if h^8z^5 is a factor of both, and then realizing that it's not a factor of the second h^7z^6
also be careful about using the word equation
there is no equation here!
So the highest common factor is h^7 and z^5?
So what would I need to do to find the hcf?
that is the hcf, you basically found it, you looked for the min exponent in both variables, identified them correctly, and now the hcf is h^7z^5 (read: h to the seventh times z to the fifth)
Got it! So if I were to find the hcf of 35a^2 x^4 and 25a^3 x^6 I would do the same thing?
yes, this one is slightly different because you now have numbers out front, right? but do the variable part first, and then the number part after
Got it, so i would find the hcf of 35 and 25 which is 5?
and then find the minimum exponent for each variable?
yep
so a^2 and x^4
So would it be 5a^2x^4?
yeah
Thank you so much!
Would it be okay to get some help for other hcfs as well?
I have a few more which are a bit tricky
sure yeah go for it
I won't say much though, you pretty much have the technique down now
L(5-2x) and 3(5-2x)
okay so treat 5 - 2x as a variable
so we can do the numbers out front first, we have 3 on the right and just a 1 on the left (remember that if there is no number in front that just means there is an invisible 1)
So you mean 1L and 3?
and then go variable by variable. if there is ever not a variable in the either expression, then just leave it out, for example you won't have any L's in your HCF
Just making sure Im looking at the same part :laugh:
1 and 3
L is just another variable
i am assuming
the 1 is literally always there. L(5-2x) = 1* L(5-2x)
Got it
just making sure we are looking at the l
1x5 and 1x-2x for the left bracket?
or do we not expand and just find the hcf?
don't expand
you can directly find the hcf, just treat (5-2x) like a variable and do what we did before
actually every time you try to find the hcf you'll try to get them in a product of terms like this
so this is like the best case we could hope for
Sorry, ive got a bit of brain fog atm. would 5-2x be the minimum variable sincw its the same in both brackets?
since
if you're saying what I think you're saying then yes..
5-2x is the variable, min exponent is 1
So how would I find the hcf?
just like before. take hcf of the numbers, which is HCF(1,3) = 1, then the min exponent of the L's, which is 0, and then the min exponent of the 5-2x's, which is 1
so overall we just get (5-2x)^1
So the hcf is (5-2x)^1?
So the simplified varsion is 5-2x?
yea
Thanks! are you any good at factorising by chance?
yes, but i have to go to sleep, it is 4 am and i have to be up in the morning
ahh, sorry to be using your time like this!
other people here are also good at factoring though
no it's okay, i like doing this
i like doing math help in my free time it's fun.
I just get carried away sometimes and stay up too late :P
good luck factorizing though.
Thank you so much, Ive been very sick for the past term and havent been able to come to lessons! (+ we got a new teacher)
This has significantly helped me 🙂
lol yeah that can be really discouraging. hopefully you are not too far behind, i know that it can be rough in that situation
Not too far behind not that youve helped me!
Thanks so much again!
How do I factorise 14l^5 +8l^4 g^4
<@&286206848099549185>
Could you help break that down for me?
im sorry, i dont seem to be catching on. Could we try k(-6+y^2) +5a (-6+y^2)
is v^2-13v
trinomial
<@&286206848099549185>
Why is it trinomial?
would 2d^2+34 be the same then?
So thats also both quadratic and trinomial?
same with -6x+36?
but not with y^2?
<@&286206848099549185>
is y^2 quadratic and trinomial?
so all of those are quadratic and trinomial?
@drifting oar Has your question been resolved?
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Is the factorised version of 25n^2-25 = 25 (n-1)(n+1)
yes
is the factorised version of 25q^2-f^2 = (5q+f)(5q-f)
yes
is the factorised version of 25t^2-25h^2 = (t+h)(t-h)
Is the factorised version of 4c^2n^2-49v^2 = (2cn+7v)(2cn-7v)
@drifting oar Has your question been resolved?
,iamnot helper
Removed the Helpers role from you.
,w factorize 25t^2-25h^2
almost
,, (t-h)(t+h) \cdot 25
938c2cc0dcc05f2b68c4287040cfcf71
,w factorize 25q^2-f^2
I think you get the idea
this is called difference of squares I think
,w factorize 14a^5+8a^4b^4
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how would i intergrate y? so far im at $3 \int \frac{1}{u}dx => \frac{(4x+1)^{\frac{1}{2}}}du = dx => 3 \int \frac{(4x+1)^{\frac{1}{2}}}{2u} du$ but i feel like theres an easier way of doing this
morphine_addiction
hold on this latex is buggin
ok... I think you forgot the square root or did you let your $u = \sqrt{4x+1}$?
ok... suppose you let your $u = \sqrt{4x+1}$. What is your $du$?
actually, you have it already
ye 2(4x+1)^(-0.5)
one trick to make this simpler is to see that $u^2 = \sqrt{4x+1}$ then, $dx = \frac{u}{2} du$ but let's stick with what you have for now
well, you will have a similar result anyways but with different bound
u mean u^2 = 4x+1?
yes. it is the same with what you did
just write it in different way.
Anyways, I think you forgot square root on 3 and your solution should be fine
but like how do i carry on from where i left of bc the (4x+1) is still in terms of x
well, you know that $u = \sqrt{4x+1}$
then your $du = \frac{2}{(4x+1)^{\frac{1}{2}}} dx = \frac{2}{u} dx$
do you agree?
yes
Then, your integral will simplify to ...
1/2
exactly
so 3x/2?
i mean u
still... really close
oh ye when i took out 3 it was supposed to be sqrt(3) so it would be sqrt(3)/u
well, no. But yes, you should have $\sqrt{3}$
it is $\left.\frac{\sqrt{3}u}{2}\right|_{a}^{b}$
hold on im buggin, 1/2(sqrt(3)*u
yes.
Now, you need to find the boundary with respect to $u$ (or just substitute $x$ back) and you should be done
so b=9, a=1?
yes, if you use $u$ that is
so $\frac{\sqrt{3}u}{2}\right|{1}^{9}$ is the same as $\frac{\sqrt{3}(4x+1)^{\frac{1}{2}}}{2}\right|{0}^{20}$?
morphine_addiction
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yes.
how come my calculator gives different answers for both?
left side, you are basically putting the $x = 0$ and $x = 20$ down already and the right side is you have not done anything yet.
and $x = 20 \rightarrow u = \sqrt{81} = 9$
you should get the same result
ye i cnaged the bounds here and got different results
well, you can't get different result when left side (u) is the second step of the right side (x)
so, for $u$, $\frac{9\sqrt{3}}{2} - \frac{\sqrt{3}}{2} = \frac{8\sqrt{3}}{2} $
for $x$, $\frac{\sqrt{3}}{2}(4(0) + 1)^{\frac{1}{2}} = \frac{\sqrt{3}}{2}$
and $\frac{\sqrt{3}}{2} (4(20)+1)^{\frac{1}{2}} = \frac{9\sqrt{3}}{2}$