I cant understand what are you saying
#help-13
crisp flint
worn lichen
dusky plume
Troll because -3 + 3 = 3±3 ?
-3 + 3 = 3 - 3
crisp flint
왜요 3 ± 3과 -3+3은 같아요?
아님니다
crisp flint
네
cedar kilnBOT
@crisp flint Has your question been resolved?
crisp flint
Also link?
hidden osprey
what
crisp flint
Whats it
crisp flint
What and why
hidden osprey
bodmas is the order of operations
2+ 6/3 = 4
2 + 6/3 ≠ 8/3
we do division before we do addition
crisp flint
2 + 6 = 8 and \frac{2 + 6}{3} = also 8
hidden osprey
yes
but 2+6/3 doesnt equal 8/3
(2+6)/3 = 8/3
anyways
this is the first thing you should know
for example 23+7 = 7+23
2+4=4+2
crisp flint
Isnt it for only multiply
crisp flint
Yes but not for negative number
hidden osprey
yes it applies for negative numbers
i will show you
4 + (-3) = (-3) + 4
4+(-3) = 4-3 = 1
(-3)+4=-3+4=1
crisp flint
Isnt it 4 ±3
hidden osprey
Isnt it 4 ±3
4+(-3) is not equal to 4 ± 3
± means plus OR minus
do you know why we use ±?
crisp flint
For something like ±3² = 3
crisp flint
e ^ ln(4)/2
hidden osprey
hidden osprey
e ^ ln(4)/2
yes
hidden osprey
this equals 2 right?
crisp flint
I cant actually find value because e is endless
hidden osprey
I cant actually find value because e is endless
lol no need to
crisp flint
i cant still find value
crisp flint
Its something like 1.9837
hidden osprey
hidden osprey
Its something like 1.9837
wraith daggerBOT
아리스킨충∪
crisp flint
When e = 2.723
hidden osprey
**아리스킨충∪**
did you use newtons method for this
hidden osprey
hidden osprey
Because ln(x) \approx 5.446
you dont need to do this
crisp flint
Is there a better way to calcalute sqrt
hidden osprey
Is there a better way to calcalute sqrt
im not asking you to calculate sqrt(4)
crisp flint
What
hidden osprey
crisp flint
Im not robot to do that so fast
crisp flint
I'm human and i cant do more length than 2.723 as e
hidden osprey
you dont have to use e
look
everyone knows that sqrt(4) is 2
you dont need to calculate sqrt(4)
do you know that 1+1 = 2?
crisp flint
Yes
hidden osprey
do you need to explain why 1+1 = 2
crisp flint
Because 1x + 1x = 2x in all way
crisp flint
i cant understand
hidden osprey
2^2 = ?
hidden osprey
2^2 = 2*2 = 4
hidden osprey
that is what i did here
crisp flint
I cant understand
crisp flint
Does it mean square root means function to find anything to second power equals to x
hidden osprey
read this
hidden osprey
and then read this
crisp flint
I got it
hidden osprey
the problem with this is that it does not show us -2
-2 is also the square root of 4
crisp flint
But log(-2) does not exist
hidden osprey
ok
so
when we want to write the roots of 4
which are 2 and -2
we have to use another symbol
±
this is the use of ±
crisp flint
But nothing to second power equals to -2
hidden osprey
that is not what it is saying
hidden osprey
But nothing to second power equals to -2
it is saying that 2 or -2 is the square root of 4
crisp flint
Is it still -2
hidden osprey
are they asking how many pairs can exist where x is an integer
livid hound
Is it still -2
is what still -2
cosmic steppe
But nothing to second power equals to -2
Well there's sqrt(2)i
hidden osprey
Well there's sqrt(2)i
i think that will cause more confusion lol
hidden osprey
It cant be
we arent doing log(-2)
crisp flint
2 ^ -x > 0
hidden osprey
yes
hidden osprey
2 ^ -x > 0
(-2)^2
hidden osprey
listen the point of this was to show the use of ±
it is used to note the two square roots of a number
in this case, 4 has two square roots
2 and -2
because 2^2 = 4
and (-2)^2 = 4
3±3 isnt really used
but what it could mean is
3±3 = 6,0
but 3±3 does not equal -3+3
like i said earlier
a+b=b+a
likewise, a+(-b)=(-b)+a
livid hound
can you restate your problem as clearly as possible?
crisp flint
Trying to find answer of this
hidden osprey
the question asks how many ordered pairs are there right?
hidden osprey
the question asks how many ordered pairs are there right?
Where x is an integer
right?
where a c and x are integers ight?
crisp flint
Yeh
livid hound
newtons method is a method involving calculus to approximate roots, usually applied where you can't determine them algebraically,
so not really something you should be using here
crisp flint
With Newton's method?
hidden osprey
With Newton's method?
if someone asks you to find the square root of 16, you wont use some complicated method to solve for it
you will immediately look at it and see that the square root of 16 is 4
or -4
crisp flint
Idk how
hidden osprey
(-4)^2=16
livid hound
the principle root is implied when mentioning just square root
hidden osprey
the principle root is implied when mentioning just square root
oh ok ill be more clear
When someone asks you to find the square roots of 16, then you will immediately recognize that 4 and -4 are the square roots of 16.
livid hound
there are two square roots of 16,
the (principal non-negative) square root of 16 is 4 (only): sqrt(16) = 4
the negative square root of 16 is -4: -sqrt(16) = -4
(saying the square roots of 16 are -4 and 4 would be valid)
dusky plume
4 x 4
dusky plume
When someone asks you to find the square roots of 16, then you will immediately ...
-16
dusky plume
there are two square roots of 16,
the (principal non-negative) square root of 16...
Yea exactly
dusk finch
My bad i saw ^ as x
||still not -16||
livid hound
-4*2 isn't -16 either
dusky plume
Lol internet
dusk finch
Bro stop using * as power
||It's actually multiplication||
hidden osprey
This formula shows the roots of the equation ax^2 -20x +c =0
Find when x is an integer given that b = -20
dusky plume
||It's actually multiplication||
He used it as power
hidden osprey
dont let him distract you
this place is a chasm of voices and mental anguish
everytime i send a message here
i lose a fraction of myself
hidden osprey
This formula shows the roots of the equation ax^2 -20x +c =0
Find when x is an i...
@crisp flint ye this should help
livid hound
note that since a is an integer,
the denominator is an integer
so for x to be an integer, the numerator would also need to be an integer and as such sqrt(b^2 - 4ac) would need to be an integer
those are the things you should start considering
hidden osprey
integer/integer is not always an integer
hidden osprey
well both terms in the numerator have to be divisible 2a
and i found that 2 could be factored out from both terms
but to get that you have to input b = -20
crisp flint
Also it wont
livid hound
what won't
hidden osprey
Also it wont
더 많은 정보가 주세요
hidden osprey
This formula shows the roots of the equation ax^2 -20x +c =0
Find when x is an i...
simplify this and then try to figure out when this equals an integer
for integers (a,c)
cedar kilnBOT
@crisp flint Has your question been resolved?
cedar kilnBOT
cedar kilnBOT
Available help channel!
light pine
cedar kilnBOT
light pine
for the avg velocity i did this
but the ms says this
im confused
could someone clarify plz whether im incorrect or not?
<@&286206848099549185>
turbid bone
To convert miles to meters you need to multiply by 1610, not divide
light pine
light pine
To convert miles to meters you need to multiply by 1610, not divide
do u agree with my answer now?
it still differs from the ms
turbid bone
but the ms says this
The velocity here is given is miles per hour.
light pine
The velocity here is given is miles per hour.
they say 4/3
thats a mistake right
should be 3/4
outer carbon
Is there a formula which, when used in a loop with x going from 0 and counting up one each iteration… given the desired number n will output 0 to n then back down to 0?
Like say if n is 5… the output of the loop as x iterates from 0 onward, will output 0 1 2 3 4 5 4 3 2 1 0 ?
quartz frost
for i in range(n+1):
print(i)
for i in range(n+1):
print(5-i)
this would be it in python i guess
outer carbon
Yeah… I was hoping for a way to do it in one loop
Sort of like how you can get 0 1 2 0 1 2 by doing x % 3
reef crown
or we can loop through to 5 and append it in list then reversely adding it to save some memory
dusk finch
I guess it should be possible with abs
echo kite
how do i do this question in math
how do i do this question for math it says 1 cm represent 4m
Write each scale as a ratio in lowest term8. 1 cm represent 4 m
outer carbon
I guess it should be possible with abs
Any idea how?
quartz frost
we could define a function for that:
f(x)=-|x-5|+5
then we would do:
for i in range(2n+1):
print(f(i))
outer carbon
Rude @echo kite hijacking my question 😳
dusk finch
dusk finch
we could define a function for that:
f(x)=-|x-5|+5
then we would do:
for i in ra...
Actually the definition of f(x) would matter on n
outer carbon
I was racking my brain trying all sorts of stuff with modulus… division… sine or cosine….
Totally forgot about the absolute value.
quartz frost
Actually the definition of f(x) would matter on n
true
outer carbon
n-abs(x-n) right?
echo kite
Rude <@759224099540828220> hijacking my question 😳
wdym
echo kite
how do i do this question for math it says 1 cm represent 4m
Write each scale as a ratio in lowest term8. 1 cm represent 4 m
<@&286206848099549185>
cedar kilnBOT
@echo kite Has your question been resolved?
echo kite
no
cedar kilnBOT
@echo kite Has your question been resolved?
cedar kilnBOT
@echo kite Has your question been resolved?
stuck granite
idle question
cedar kilnBOT
idle question
stuck granite
I watched 3b1b's video on exponentiating matrices
say, we have $e^{M}$, no $\pi$ or $i$ for now. What does it really mean?
wraith daggerBOT
Awesome_Ruler_007
stuck granite
That's what the whole video was about, but in the end, that relation of:
$\frac{d}{dt}x(t)=Mx(t)$ having $M=e^{Mi}$ was just unintuitive, and mathematical rather than proof-y
wraith daggerBOT
Awesome_Ruler_007
stuck granite
I understand linear transformations, how $i^n$ are just $n$ successive transformations, happening to be the 90 deg rotation. But I still don't get what exponentiating that even means
wraith daggerBOT
Awesome_Ruler_007
cedar kilnBOT
@stuck granite Has your question been resolved?
civic elk
Duno if this question fits or not, so next week I have a accuplacer for pre calc subject, and idk where to start studying for it, I’ve heard it has algebra 1 and 2 with a little bit of pre calc
civic elk
Nope they haven’t given anything, and the algebra 1,2 and pre calc I learned from my freind who took it last year, I even asked my teachers and they said they didn’t know
civic elk
they should give you a list of the contents
I did find smth called common core rewiew, I don’t think it’s related but it’s only for Algebra 2, so ig I’ll study it then try to find pre calc vids on yt
.close
cedar kilnBOT
cedar kilnBOT
Available help channel!
iron loom
I know you can write a system in terms of vectors when the variables are to the power of one but when they are not what do you do?
hollow osprey
I know you can write a system in terms of vectors when the variables are to the ...
notice the inherent symmetry in the equations, you might start with something like adding all 3 equations to each other
in general you probably can't solve an arbitrary system of 3 nonlinear equations, but in this case you can because the second and third equation is simply the first one but applying the shift x -> y, y -> z, z -> x
silent badger
Did I do rhis correctly, and how would you do question 2
cedar kilnBOT
Did I do rhis correctly, and how would you do question 2
cedar kilnBOT
@silent badger Has your question been resolved?
feral osprey
Can anyone explain why
lim(xa^-x) = 0
as x approaches +inf and a ≥2 ?
latent bloom
Okay
lethal jackal
does it not work for x > 1?
latent bloom
$\lim_{x \to \infty} xa^{-x}$
wraith daggerBOT
VulcanOne
gritty viper
feral osprey
a is a real number that's greater than or equal to 2
latent bloom
But it shouldn't matter much. The question has a>=2
Okay so
Here since a is a constant bigger than 2
And it is in an exponential function
It is known that exponential functions outpace linear functions
So
$\lim_{x \to \infty} \frac{x}{a^x}$
wraith daggerBOT
VulcanOne
feral osprey
Oh that makes sense why it's equal to 0
latent bloom
You will see a^x race to infinity faster than x does
Making it reach 0
That's using the list of functions
feral osprey
Yeah, I get it now, thank you so much!
latent bloom
You can also prove it using L'Hopital but it's not my cup of tea
feral osprey
I can't use L'Hopital, but that'll work.
latent bloom
Yeah
feral osprey
Thanks again.
latent bloom
feral osprey
.close
calm hedge
A smal printing company produces the printed menus for a take away restaurant. The charge for a print run is $80 plus 30 cents for each menu printed. Construct a cost function that describes the charge( indollars) for such a print run
short blade
yes
calm hedge
also
my teacher said that "if it isnt an function, dont even bother, its done"
i dont know what that means
i forgot in what context
short blade
i don't either without more context
calm hedge
but even if the graph isnt a function, dont you still do the question
wait lemme just have a look back at it
velvet mortar
but it's a good idea to include C(n) to show C is a function of n
Calc textbooks be like y = y(x)
short blade
one of my profs made a variable substitution and ended up writing:
u = u(x,y) = u(alpha, beta)
which is like not true
calm hedge
well i dont know the context but thanks for confirming with me
also
my friends kinda showed me something new
he said that we dont get taught the insight of topics
like say for
d/dx = 2x (this is his example)
and i said, use the power rule, then he said
why
short blade
d/dx = 2x?
calm hedge
so with the interpretation of maths formulas
short blade
do you mean dy/dx?
calm hedge
so with the interpretation of maths formulas
should we know the interpretation
velvet mortar
d/dx = 0 right?
short blade
it's probably a good idea to
calm hedge
like i kind of figured out how the formulas of simple shapes came to be
short blade
d/dx = 0 right?
d/dx is an operator
calm hedge
but it took years to make me realise
short blade
you should be familiar with the limit definition of a derivative
and the geometric intuition
which is why we think of a derivative as the slope at a point
calm hedge
but even if i have a good interpretation, would it help me in tests in anyway, cause friend said teachers dont give a fuck about your knowedlge, its just formulas
calm hedge
idk if learning the interpretation of each formulas is worth the time
short blade
but even if i have a good interpretation, would it help me in tests in anyway, c...
it does help in tests
if you memorize formulas then you don't actually understand the math
calm hedge
yeha
short blade
if you understand the math, memorization is kind of not needed
the intuition will be there
calm hedge
like i memorised the quadratic formula
but i dont know how it came to be
same for many other shapes formulas
short blade
this should be your intuition for a derivative
that's a pretty bad gif
this is probably better
short blade
so when they ask you for the slope of a tangent line, you can see it's just the derivative at that point
calm hedge
if you solve the area of this with the.. idk what the formula is but its like putting infinitely small lines infinitely alongside eachother to find out the area
short blade
if you solve the area of this with the.. idk what the formula is but its like pu...
that's an integral
short blade
it's the limit of a riemann sum as the number of squares goes to infinity
velvet mortar
Intuition for the weak, real mathematicians use pure reason
short blade
no
short blade
infinity is an abstract concept
you'll be adding infinitely many, infinitely thin slices
calm hedge
yes
short blade
it's not because it's a curve
velvet mortar
Infinity is beyond our capability, only gods can be grasp it
calm hedge
Infinity is beyond our capability, only gods can be grasp it
📣
oops
i tried to find an emote for mega brain
anyways
short blade
you should have geometric intuitions for calculus (if that helps you)
i find that thinking of calculus geometrically makes it magnitudes easier
velvet mortar
you should have geometric intuitions for calculus (if that helps you)
No, that's a bad way to learn
You should avoid intuition at all cost
short blade
they're kidding
yes
if you're given this
it's quite difficult to actually understand what you're doing
short blade
but with this, the intuition is clear
short blade
a good teacher/professor will explain where a math concept comes from
and not just drop it on you
calm hedge
mine never does
calm hedge
but with this, the intuition is clear
but
even if you have the intuition, dont you still have to use the formula whether you know it or not
calm hedge
alright
short blade
you should understand mathematics, but work with it rigorously
the intuition should be there, even if when you're doing math you have to use symbols
people didn't just mess around with limits until the derivative definition popped up
they used geometric intuition and then defined the derivative from there
cedar kilnBOT
cedar kilnBOT
Available help channel!
fallen kestrel
cedar kilnBOT
thin topaz
start with finding the intervals
thin topaz
not sure where to start
did u get it yet??
fallen kestrel
i think i need to use simpsons rule
so do i start with finding change in x?
im confused w what you mean with finding the intervals
thin topaz
you need to split the graph into n=12 intervals and calculate the approximate area under the curve using simpson's rule for each one of them
and then sum the results up and divide for the final result, which is an approximation ofthe average temperature
we expect the result to be somewhere close to 70
fallen kestrel
so how do i use the simpsons rule formulas to do that
fallen kestrel
which are 0 and 24 right?
thin topaz
right. but it says use n=12
so you have to cut your graph into 12 pieces and apply this formula 12 times
it would be 0 and 24 if n=1
basically make a table
one column should say t = 0,2,4....
one would have f(t)
fallen kestrel
would change in x be 2?
thin topaz
basically different forms of the same formula
thin topaz
nope
it has to be 2/6 * [ (f(0) + 4f(1) + f(2)) + (f(2) + 4f(3) + f(4) ) + ..... f(22) + 4f(23) + f(24) ]
thin topaz
okay... so what is Δx ?
fallen kestrel
2
thin topaz
are you sure?
fallen kestrel
i asked before and you said yes
thin topaz
alright 2/3 seems correct now indeed
however the sum is still wrong, you haven't included information from the whole day I think
fallen kestrel
well i incremented by 2
becasue our change in x is 2, so x1=2, x2=4, x3=6, etc
is this right?
fallen kestrel
yea i think i wouldve gotten same answer is a and b were 12
and i divided by 12 at the end
.close
cedar kilnBOT
cedar kilnBOT
Available help channel!
jade stag
huh
jade stag
so the limit is that "ratio of the leading coefficients?"
you dont find out the domain through the denominator?
digital cliff
yeah, it can be seen, when the degree of the num and denom is n if you multiply by $\frac{\frac{1}{x^n}}{\frac{1}{x^n}}$
oof 1 sec
jade stag
no worries azo
wraith daggerBOT
AℤØ
jade stag
appreciate you for helping me with this ❤️
digital cliff
when you do that youll see that everything other than the leading coefficients will be over some power of x so they tend to 0
digital cliff
its the same as multiplying by 1, yeah
like if you look at the first example
if you multiply both the numerator and denominator by 1/x^2, everything other than 3 and 4 will be over some power of x
so those terms tend to 0 leaving you with just 3/4
jade stag
1/x^2 times 5x = 5x/x^2, which is 5/x not 0?
digital cliff
but as x tends to + or - infinity 5/x tends to 0
jade stag
and 7 times that would be 7/x^2 not 0?
digital cliff
but as x tends to + or - infinity 7/x^2 tends to 0
jade stag
how do they tend to 0
digital cliff
whats the lim as x approaches infinity of 1/x?
jade stag
1/x^2 times 5x = 5x/x^2, which is 5/x not 0?
ngl this is weird way to look at it in my eyes
multiplying num and denom by fractions
could get messy real quick
not prepared for that rn
digital cliff
huh
in this case it wont, this is just a simple kind of manipulation you can do that makes this more clear generally.
plus, when youre doing this in regards to situations like this, i dont think it would every get very complicated for the thing im talking about
digital cliff
whats the lim as x approaches infinity of 1/x?
though it kind of hinges on you understanding this
digital cliff
whats the lim as x approaches infinity of 1/x?
im not multiplying by anything rn this is seperate from the question,i just want to check you know the answer to this
digital cliff
wdym only numbers?
jade stag
-inf, positive inf
oh
mb
the answer
to ur question
is 0
bcuz infinity
is large
digital cliff
but as x tends to + or - infinity 7/x^2 tends to 0
yeah, thats what i mean by this stuff
digital cliff
if you multiply both the numerator and denominator by 1/x^2, everything other th...
when?
jade stag
to me
jade stag
its the same as multiplying by 1, yeah
how is this same as that
digital cliff
because anything over itself =1, 5x/5x=1, 54/54=1 (1/x^2)/(1/x^2)=1
it just means its a valid manipulation you can do to a fraction without changing its value- multiplying the denominator and numerator by the same value
jade stag
5x turning into 1
is not natural
anyway it never got to that though, since we did times 1/(x^2)
digital cliff
is not natural
yeah, im not sure what you mean though
5x doesnt turn into 1
its just 5x divided by itself is 1
jade stag
5x/x^2 = 5/x that isnt 1 over 1
digital cliff
i never said 5x/x^2
i said 5x/5x
i was just showing that any value over itself is one
digital cliff
okay lets back up😅
jade stag
ok
digital cliff
**AℤØ**
are you okay with accepting that doing this wont change the value of the fraction
digital cliff
i was just showing that any value over itself is one
due to this
digital cliff
hm okay i can kinda show it 1 sec
we can firmly say that $\frac{1}{x^n}=\frac{1}{x^n}$ right? by the definition of '=', if we divide both sides by $\frac{1}{x^n}$ we get $\frac{\frac{1}{x^n}}{\frac{1}{x^n}}=1$
wraith daggerBOT
AℤØ
digital cliff
a value divided by itself is always 1 (except for 0)
i know it might look weird because its fractions over fractions but its the same as saying 5 divided by 5 is 1
jade stag
x^n/x^n = 1 yea
digital cliff
yeah, this is the same
so (1/x^n)/(1/x^n)=1
thats why its valid to multiply a fraction by it
digital cliff
ah okie dokie, now we get to the key part
digital cliff
when you do that youll see that everything other than the leading coefficients w...
this, and the message above it ig too
digital cliff
1/x^2 times 5x = 5x/x^2, which is 5/x not 0?
i can write it out for one of the examples if itll help to see. Here you were right with the multiplication but i never said 5x/x^2=0 i said its limit as x approaches + or - infinity is 0
digital cliff
ah okay it may take me a couple minutes
digital cliff
$\frac{3x^2+5x-7}{4x^2-2x+1}=\frac{3x^2+5x-7}{4x^2-2x+1}\cdot\frac{\frac{1}{x^2}}{\frac{1}{x^2}}=\frac{3+\frac{5}{x}-\frac{7}{x^2}}{4-\frac{2}{x}+\frac{1}{x^2}}$ as x approaches $\pm\infty$ you can see that every value that is over some power of x is going to tend to 0. leaving us with $\frac{3+0+0}{4+0+0}=\frac{3}{4}$
wraith daggerBOT
AℤØ
digital cliff
no problemo
cedar kilnBOT
cedar kilnBOT
Available help channel!
gleaming summit
Can I get some help explaining this
cedar kilnBOT
Can I get some help explaining this
gleaming summit
<@&286206848099549185>
humble marsh
Can I get some help explaining this
which part are you stuck on?
gleaming summit
Stuck on the simplifying, on how it goes from 2-3p+(p-3)(p-1)/(p-1) how does the extra p-1 get there, and then when simplyfying how does it equal p(p-2)/p-1
dire geode
Stuck on the simplifying, on how it goes from 2-3p+(p-3)(p-1)/(p-1) how does the...
From or to that first fraction in your sentence?
gleaming summit
In the first fraction I mention, how does the p-1 on the numerator get there
dire geode
In the first fraction I mention, how does the p-1 on the numerator get there
Common denominator of the previous line
gleaming summit
How can you just add it to the equation
gleaming summit
My algebra is so rusty
dire geode
Like expressing 2/3 + 3/4 as a single fraction
cedar kilnBOT
@gleaming summit Has your question been resolved?
cedar kilnBOT
@gleaming summit Has your question been resolved?
gleaming swift
hey
tame wraith
!status
cedar kilnBOT
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'm told it's wrong
4. I got an answer and would like my work checked
5. I have a question about someone else's worked solution
6. None of the above
hmm, question a is kinda wierd
gleaming swift
yea
tame wraith
for b c d e yh
gleaming swift
and the answer is unknown so yea
gleaming swift
for b c d e yh
oh i see then is it ok if you can just help me out for those questions
tame wraith
what is the range of acos(x)
tame wraith
what is the range of acos(x) + b
tame wraith
ok yh
so now
find what values of t
gives you 9
and what values of t gives you 1
gleaming swift
oh so put the equation in the middle and do inequalities?
gleaming swift
and what values of t gives you 1
oh ok so that gives me maximum and minimum
i see
and then for c i just do when its 5?
gleaming swift
i mean d sorry
tame wraith
oh so put the equation in the middle and do inequalities?
no
oh wait you know that
the shortcut is that
when its 9
its because
cos(2pi t/3) = 1
and when its 1 its because cos(2pi t/3) = -1
gleaming swift
oh ok yes
and you said you knew how to do D as well
can you please help me out for that to if you cann?
.close
tired inlet
can someone help me with this problem
cedar kilnBOT
can someone help me with this problem
tired inlet
Calculate the energy a hydrogen electron would have to absorb to jump up from energy level 1 to energy level 2
fair geyser
slow thicket
^
tired inlet
but do I use f = cR(1/nf^2 - 1/ni^2)?
distant cedar
@tired inlet ☝️ Please search more on Google if you have additional context to add. This is not a chemistry server unfortunately.
karmic cedar
Chem!!
slow thicket
Physics, math same thing.
No
lyric narwhal
Physics, math same thing.
excuse me?
stray otter
Chemistry
calm hedge
💀
tired inlet
no but seriously I got the answer to the question but I'm just not sure how to actually get to that answer
the answer is 1.64x10^-18 J
tired inlet
I can't use google to find out how to get the original answer
calm hedge
this is a maths server
slow thicket
Ofc you can
distant cedar
I can't use google to find out how to get the original answer
Learn to then
lyric narwhal
maybe try asking in a chemistry server instead of a math server..?
fair geyser
it's not a math question what to use
but it is a google question
i don't understand what you expect from us
cedar kilnBOT
@tired inlet Has your question been resolved?
cedar kilnBOT
cedar kilnBOT
Available help channel!
elfin otter
Question:
Solve
cedar kilnBOT
Question:
Solve
dire geode
Use the formula for nPr
elfin otter
Question:
Solve
This one
elfin otter
Is what I got so far
This is the working I hv so far
But idk what went wrong
twin temple
did you compare your answer with mark scheme ?
elfin otter
This is the marking scheme
twin temple
wait a sec im working on it
elfin otter
Ye I just realised
elfin otter
Is what I got so far
Is this correct so far?
livid hound
yes
elfin otter
Ok now I have:
n (n-2) ! (4n-2) = 10n
twin temple
did you get 10n/n!
elfin otter
did you get 10n/n!
It's 'solve', not prove sry
twin temple
ik that
elfin otter
(n-2) ! (4n-2) = 10
How do I proceed from here?
fleet shoal
put the value of n in it ..sorry i misunderstand..
elfin otter
put the value of n in it ..sorry i misunderstand..
How?
No shot I hv to try every single digit
twin temple
Do u know the value of n @elfin otter
elfin otter
Answer says n=3
livid hound
wait, 1 sec
twin temple
10/3
elfin otter
This is the plain ques
cedar kilnBOT
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Available help channel!
eager remnant
cedar kilnBOT
eager remnant
Could someone please remind me how to draw the graphs of f’(x) and f’’(x) ?
livid hound
knowing the equation for the original function,
you can just differentiate
you should have no issue graphing the derivatives of this
eager remnant
You’re right, that should have been obvious
lyric narwhal
Could someone please remind me how to draw the graphs of f’(x) and f’’(x) ?
there isn't a specific way to draw the graphs of f'(x) or f''(x)
it depends on the original function
eager remnant
I MENT for this one specifically, i forgot that I can just differentiate for the new graph
buoyant latch
you could draw a graph with no scale markings on the axis and just write y'
eager remnant
cedar kilnBOT
eager remnant
The shapes of f’(x) and f’’(x) are correct but the positioning is wrong
Was wondering whether this was important
Also, could someone explain to me the points of inflection
Both stationary and non-stationary
From my understanding points of inflection are when the differentiation of a function = 0
<@&286206848099549185>
nimble veldt
From my understanding points of inflection are when the differentiation of a fun...
.... are when the second differentiation of a ...
eager remnant
Sorry i don’t follow
When the second differentiation of a function = 0?
Wait this makes sense
Ok
But what about the difference between stationary and non stationary points of infliction?
nimble veldt
eager remnant
Ok this makes sense
But regarding stationary and non stationary what’s the difference
nimble veldt
eager remnant
Ok makes sense
What about the positioning of my graph
Like my porabola is a lot higher in my answer than the textbook answer
nimble veldt
where there given values for the graph? I cant see them. so the position relative to y-axis isnt relevant if you discuss maxima, minima and/or inflection points
think about this: a shift up or down relative to the y-axis is a +C term, like x^2+4 or x^2-4m and this +C disappears by differentiation. so for maxima, minima, etc. it is irrelelvant.
trim crescent
Just a quick question, when we have a series like this with n>=0, we should consider that we’re looking at the limit of this series right ? So we could replace the series with the sum from n=0 to +oo, same thing right ?
crimson delta
just other notation, yes
$\sum_{n\geq 0}$, $\sum_{n\in\bN}$, $\sum_{n=0}^\infty$ etc all mean the same thing
wraith daggerBOT
Denascite
trim crescent
Great teachers never defined it but regularly use it, just wanted to make sure
Okay great i see
crimson delta
maybe didnt think it was worth mentioning
trim crescent
And when we only have the sum symbole, same thing ?
crimson delta
just $\sum$ ?
wraith daggerBOT
Denascite
trim crescent
Yep, there’s one example just above on the picture i sent
crimson delta
depends on context but probably yes
just too lazy
although that's more a thing I would expect handwritten, not typed
trim crescent
Haha yeah okay thx man, take care !
crimson delta
often you would also just use $\sum_n$
wraith daggerBOT
Denascite
trim crescent
Got that one too haha
But in that case they definitely need to define n to know where to start
Thx again ❤️
.close
cedar kilnBOT
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Available help channel!
mossy sequoia
The limit of √(12-x)-3/√(7-x)-2 as x approaches 3
cedar kilnBOT
The limit of √(12-x)-3/√(7-x)-2 as x approaches 3
mossy sequoia
so, when i try substitution, the denominator becomes 0
south tundra
You mean $\lim_{x\to3}\frac{\sqrt{12-x}-3}{\sqrt{7-x}-2}$?
wraith daggerBOT
A Lonely Bean
mossy sequoia
You mean $\lim_{x\to3}\frac{\sqrt{12-x}-3}{\sqrt{7-x}-2}$?
yes
south tundra
so, when i try substitution, the denominator becomes 0
Yeah, and the nominator approaches 0 as well
I suppose you are supposed to multiply by the conjugates
mossy sequoia
I suppose you are supposed to multiply by the conjugates
yeah, this is what i did, but it became complicated when i had to multiply squareroots on squareroots
south tundra
Alright, let me try then
half forge
I suppose you are supposed to multiply by the conjugates
you need to multiply the conjugates of both the numerator and denominator
south tundra
That is why I said conjugates in plural form
mossy sequoia
That is why I said conjugates in plural form
i ended up with 3-x(√ (7-x)+2)/3-x(√ (12-x)+3)
did i do it correctly?
south tundra
Let me check, one moment
You mean $\frac{(3-x)(\sqrt{7-x}+2)}{(3-x)(\sqrt{12-x}+3)}$, right?
wraith daggerBOT
A Lonely Bean
mossy sequoia
yes
south tundra
Yup, correct, note that you can also cancel out the (3 - x)'s
mossy sequoia
ok, so if i subsitute right now, how do i squareroot 10
half forge
you got sqrt10? 
south tundra
Where is sqrt(10) coming from?
mossy sequoia
well isnt 7 - x = 10 since the limit was approuching 3?
south tundra
-x = -3
mossy sequoia
ahh no never mind
i missread the minus as a plus
after substituting, i got 6/6 which is the same as 1
thats the final answer right?
half forge
no, the numerator is not 6 when you substitute x=3
half forge
you can simplify 4/6 further
mossy sequoia
2/3 then
half forge
yeah
cedar kilnBOT
spiral steeple
Can anyone help me solve b
i have the answer of a if you need or if u need anything else
cedar kilnBOT
cedar kilnBOT
Available help channel!
merry cargo
how do i solve a question when theres a given like what i encircled
livid hound
depends on what other info you're given
livid hound
what specifically are you told about these angles
merry cargo
theyre supplementary angles
livid hound
do you know what supplementary means?
merry cargo
something about completing the angle
livid hound
no
merry cargo
oh
merry cargo
oh
cedar kilnBOT
@merry cargo Has your question been resolved?
severe edge
cedar kilnBOT
severe edge
i want to convert this into an expression with normal units
so going from decibles per decade to standard units
so X decibles is equal to 20logS where log is base 10 and S is the standard units
so this graph currently is 20 decibles/decade
but my math skills arnt sharp enough to know how to deal with the x axis which grows exponentially
blissful glade
cedar kilnBOT
@severe edge Has your question been resolved?
cedar kilnBOT
cedar kilnBOT
Available help channel!
odd lily
I'm a bit confused, why isn't a) (2, -6, 1)?
cedar kilnBOT
I'm a bit confused, why isn't a) (2, -6, 1)?
quartz frost
well, they have a system of linear equations and put them into a matrix
odd lily
well, they have a system of linear equations and put them into a matrix
Then they wiped it clean, but how do youg get (1,3,-4) out of that?
cedar kilnBOT
@odd lily Has your question been resolved?
odd lily
<@&286206848099549185>
cedar kilnBOT
@odd lily Has your question been resolved?
cedar kilnBOT
@odd lily Has your question been resolved?
heavy hull
hi im stuck on part B for how to calculate the IQR
cedar kilnBOT
hi im stuck on part B for how to calculate the IQR
heavy hull
hi im stuck on part B for how to calculate the IQR
it doesnt help that the image quality is bad so it is hard to see the scale
digital cliff
you can find the second and third quartiles from the cumulative frequency: Q2 will be at 20, Q3 will be at 60 - since the total is 80
untold onyx
cedar kilnBOT
untold onyx
may anyone explain the answer? I thought it may not be subspace since p(0) might be a different number from the first polynomial that is x^0
cedar kilnBOT
@untold onyx Has your question been resolved?
oak venture
Any idea how to solve using calculus
cedar kilnBOT
Any idea how to solve using calculus
crimson sedge
integrate along the vertical
oak venture
i don't quite understand
crimson sedge
try drawing a diagram
oak venture
crimson sedge
now sum the stacked circular cross sections
(it's similar to the proof of volume of a full sphere)
oak venture
Ohhh I forgot about that thank you
crimson sedge
np
oak venture
When i sum the circular cross sections
Do I leave out the last 2 then
Like do I do it from -5 to 3 instead of all the way to 5
cedar kilnBOT
@oak venture Has your question been resolved?
pliant spire
yeah just do it from -5 to 3
cedar kilnBOT
@oak venture Has your question been resolved?
oak venture
thank you
soft ivy
I have a question on something that I'm stuck on. I've included the exact question for reference.
I ended up answering the question correctly, however, this was using "clunky" means and I would like help on how to get the answer the correct way. My method for answering the question was via the common function format of the Maclaurin series of tan^-1 (x) and then substituting in the different factors and including what I assumed would've come out of the integrand of the original function.
red pumice
,w arctan series expansion