#help-39
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Let ( f ), ( g ), and ( h ) be three arithmetic functions, and ( f^{\sim} ), ( g^{\sim} ) be the inverses of ( f ) and ( g ) respectively. Which of the following statements are correct? Check each correct proposition.
\begin{itemize}
\item If ( f ) is totally multiplicative, then ( f^{\sim} ) is also totally multiplicative.
\item If ( f ) takes values in ( \mathbb{Z} ), then ( f^{\sim} ) also takes values in ( \mathbb{Z} ).
\item If ( f ) takes values in ( \mathbb{Q} ), then ( f^{\sim} ) also takes values in ( \mathbb{Q} ).
\item The inverse of ( fg ) is ( f^{\sim}g^{\sim} ).
\item If ( f ) and ( g ) are multiplicative, then ( f \cdot g ) is multiplicative (where ( f \cdot g ) is the function associating to each ( n \in \mathbb{N}_0 ) the number ( f(n) \cdot g(n) )).
\item The inverse of ( f \cdot g ) is ( f^{\sim} \cdot g^{\sim} ).
\item If ( f ) is totally multiplicative, then ( f \cdot (gh) = (f \cdot g)(f \cdot h) ).
\end{itemize}
habibjr.
@sonic cradle Has your question been resolved?
precision: ( f^{\sim} ) and ( g^{\sim} )
are a notation for the inverse for dirichlet convolution
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hi
@drowsy edge Has your question been resolved?
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The communicating vats
I have a question
the Px in the left side is the same as Px in the right side, right?
But how can they be the same if the height for the Px on the left is twice that of the second Px?
And if they are equal to eachother, then would it be correct to consider that Py is equal to P2?
they're equal but water pressure changes with height, so P1 and P2 are different
like the deeper you go in the ocean the higher pressure you get
I see
and what about Py and P2? are they also equal to eachother?
right
Alright thank you
I got one
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Where is 91.25 coming from here?
365/4
@crimson burrow Has your question been resolved?
oh.
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yeah just like that
just with a bunch of parentheses
whenever you see a √ replace it with (...)^½
But how do I solve that
wdym solve
Well doesn’t the like sqrt1-t get sqrt like 3 times
Find derivative
Yeah but idk how to write it in exponent form
u dont have to
Then how I solve it
this is how u would continue
do you know how to calculate the derivative of square root of x?
you dont need to do that
Ok but I only know how to find deriv of sqrtx cus ik it’s exponent
And I use power rule
So without it idk how to solve
ok
take your original thing
and every time you see √stuff, replace that with (stuff)^½
you will have some nested parentheses. that's okay.
(3t)^1/2 + (2)^1/2 +(1-t)^1/2
Well that’s wrong
But idk how to write it
@unborn abyss
ok
see how there's a biiiiiiiiiig square root symbol over everything?
take the stuff inside that square root symbol
and rewrite it on your piece of paper
then
put parentheses around it
and write ½ to the top right
note: you will have other square root symbols inside of there. That's okay! we'll get to those
and let me know when you've done that and what it looks like
@spring crystal ^
Idk how to make the 1-t go to 1/2 for a third time
this is what i wanted you to write
although you might find it easier to start from the inside but still
what about the inside
you'll end up with $$(3t+(2+(1-t)^{\sfrac12})^{\sfrac12})^{\sfrac12}$$
hay²le
do you see how each layer of square root became a (...)^1/2?
compare what i wrote to your original problem
Yeah
It’s very confusing to look at
well... yes
if you're writing it on paper you can make the inner stuff smaller
to help you keep track
you do have physical paper, right?
and a pencil?
Not right now
What inner stuff
Yeah
if you were writing this in person with the pencil and paper that you should always have when doing math
then you could make the inner layers smaller
apply the chain rule
@unborn abyss am I suppose to apply this like 4 times?
should be 3 times i think
remember how the chain rule works
you should find a way to make your t's not look the same as +'s
i don't understand what you mean
to me it looks like you accurately wrote down the first part, the f ' ( g (t) ) term, and then wrote down something that wasn't really g ' (t) at all
Yeah I’m stuck on that part
The g’(t)
what's g (t)?
Plus sign only after 2
you should write your t's with hooks on them
Ok I’ll change it to x later
ok well if you do that then don't use x for multiplying
anyway
look at the original expression, i think you miscopied something
I derived the 3t
So it became 3
i think you need to review and practice simpler cases of the chain rule
why did you do that?
the inner function doesn't get differentiated in that part
That was the g’(x) part
no it isn't? isn't that the f ' ( g(t) ) part?
neatness and practice
and paper for the love of god
get some paper
i think you missed that in the original post it had a 3t + portion
somewhere along the line you dropped either the t or the + and i honestly cannot tell which one
Idk how to for this
It’s too confusing
this is simpler than the original one
what's g (t)?
you need to practice derivatives in general
hay²le
Am I supposed to bring 1/2 to the front again?
@unborn abyss
you will need to use the chain rule again yes
and the power rule
and the sum rule
,tex .diff rules
hay²le
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How do I figure out this?
how old is both sexes
,calc 10034+37101+7647
Result:
54782
so it's the column total
anyway, you focus on the northeast column and then use whatever method you were taught to find the child dependency ratio to find that ratio
I didn't understand the way the teacher explained it thats why I reached out to this chat because I didn't get it, there method was too in depth
we have no way of answering this, I reckon none of the helpers are in your class
how? I thought I could ask questions here its not like the questions sacred to the class
because we don't know what definitions you're using
The child dependency ratio is number of people under 15 / total population
and we can't access the course materials with them
how would I find that
Luckily I did geo
you would find that in the course materials
So 10034/54782
!nosols
As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.
Not relevant here as they're not struggling with the mathematics

It's a geography question that happens to use maths
that's not up for you to decide
As you said it requires outside knowledge
I fail to see how giving them the answer would stunt their problem solving in this situation
They just need to remember the definition for next time

so would the answer be 0.18312?
Looks about right
It should be around 10/50 after cancelling 1000 from top and bottom
That's how you know your answer makes sense
I can keep trying again
Oh well look in your course notes
The definition is probably different
we sadly don't have slides only sometimes pdf on zoom
Like those pdfs I mean
check the question again. It says round to the nearest thousandth
Ima try to look at his pdfs rq also so would it be 0.183?
is 0.183 rounded to the nearest thousandth?
Mhm
Yeah I think that's the issue, totally missed that
What I saw , the formula says the ratio is (population of under15+above 65)/(population of 15-64)
So it's 10034+7647/37101
Ahhh right that makes more sense
,calc 17681÷37101
The following error occured while calculating:
Error: Undefined symbol ÷37101
Yeah it's the child dependents / working age population
,calc 17681/37101
Result:
0.47656397401687
@terse stone Has your question been resolved?
@terse stone Has your question been resolved?
Try 0.476. You don't take 5 as 10 if the number preceding it happens to be even.
@terse stone Has your question been resolved?
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yo
can someone help me with my math
I can't figure out what 5x8 is
I just recently learned how to do addition and subtraction
I was wondering if anyone could help me learn math
5x8 is the same as you add 8 number of 5
a.k.a 5+5+5+5+5+5+5+5
oh that's 40 right?
Yes correct
yay
I've never been to school so I don't know any math
I've had people on discord help me with some though
oh really?
yeah
There are some free courses on Khan academy
my uncle comes over and helps me with spelling and typing sometimes
Check it out if you have time
and the school is pretty far away
it's ok man
how far is it?
I don't know
you can learn pretty much everything in your home of what they teach in school
and I'm not home schooled because they're always at work
well thanks for the help bye
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is this derivative wrong or something
it looks correct
wait which equation are they originally deriving from
isnt it P=8n-nsqrtn
from the question
@sterile tusk
where did the -3/2 come from
well $n\sqrt{n}=n^{\frac{3}{2}}$
y0shi
and they just used power rule
how does nsqrtn =n3/2
the negative was originally there so it stays
well what’s sqrt n with a fractional power?
n^1/2
y0shi
yep
yw!
dC/dx is the rate of change in the marginal cost
so if i plug in x=11 i would get how much the cost increases to get the next item
which is why we plug in x=10 to get the 11th item
is taht just always the case
C is the amount it costs
so dC/dx is the cost per item
so if i want to find how much the next item would cost
i just have to find that using the equation given
this question is a little weird in my opinion
whys it weird
so i only minus one from the x when its derivative of the cost right
@sterile tusk
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Is this vector symmetrical because the diagonals are the same
The entries on “opposite sides” of the diagonal are the same, but yep it’s symmetric
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could someone help me get the correct answer, I dont understand why mine is wrong
@sour bobcat Has your question been resolved?
Remember that matrix multiplication is not commutative, so left vs right multiplication is important.
AX(D+BX)^-1 = C
AX = C (D + BX)
AX = CD + CBX
AX - CBX = CD
(A - CB)X = CD
You've gotten this far correctly
However, now you must left multiply by (A-CB)^-1
You erroneously left multiplied on the left hand side and right multiplied on the right.
@sour bobcat ^
thnx
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Question 5 pls
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I’m trying to prove the derivative power rule using limits then prove that limit with epsilon delta but I’m stuck while on the epsilon delta part
It's a bad strategy. We prove the limit laws with ε-δ, then use the more powerful limit laws to handle the power rule
Like what
Like where
!show
Show your work, and if possible, explain where you are stuck.
@unreal flume Has your question been resolved?
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What’s with the $dxdy$ in $\iint_D f(x, y),dxdy$
Frosst
Shouldnt it be more like $d(x, y)$
Frosst
Because one integral is basically smooshed inside another integral
So the dx Integral is inside of the dy one
But that implies there’s an order that dx happens then dy
Shouldn’t $\iint_D$ and $\int_A\int_B$ be different things?
Frosst
The region D encompass the bounds of A and B
Just a shorthand
There's a theorem that proves there is no difference
when you think of it as a riemann sum that dA is like a little piece of area thats dx by dy and the sum can be interpreted / broken up to be doing two regular single variable integrals in a row and it can be shown that the order doesn't matter
except when there is 😁
Well fubini tells us if they exist then it’s the same?
fubini says if the abs val is integrable then you can integrate using iterated integrals, in either order
So iterated integrals aren’t the same thing as this double integral then
they give you the same answer under fairly general conditions but no they're not the same thing
If $D = A \times B$, then $\iint_D$ is the same as $\int_{A\times B}$?
Frosst
what's the significance here of using two integral symbols for the first and one for the second
Well I’m not too sure what this 2 integral notation means
Is it the single one by definition?
it's a sort of unfortunate classical notation, people (like in calculus classes) use it for area integrals even though it clashes a bit with the iterated integral notation
So what’s an area integral
once you get to the level of studying lebesgue integration, people typically use a single integral symbol regardless of the dimensionality of the space
this guy here
So the area integral is the Riemann integral in multidimensions
i said "area" integral but i really meant that the differential element represents area
i.e. integrating a 2-dimensional function over some 2-dimensional region
Right, people use dA rather than dxdy?
yea that's common
A for area? To represent a part of R?
in calculus books they often use the convention of not switching to dx dy until they are doing iterated integrals
after all, you can do dA in polar coordinates too for example
yea
So there’s a difference here
The double integral is riemann where the single one is lebesgue
wellll i don't know that i would automatically assume that's true, i'm sure you can find different conventions among different authors
Oh
but i'd say the use of a single integral symbol seems more prevalent once you get into the lebesgue theory
because they want to deal with integrating over all sorts of spaces
or stating theorems that apply regardless of how many dimensions, for example
Do you also then say that if it works with the lebesgue integral then it surely also works with the Riemann integral
so now you're integrating with respect to some abstract measure
Cos fubini’s theorem is for lebesgue integrals
the lebesgue integral can handle situations where the one dimensional "slices" (the ones you integrate using the one dimensional iterated integrals) wouldn't be riemann integrable
so just because you can use iterated integrals and swap their order in the lebesgue world, doesn't mean it holds for the same function using riemann integrals
for most "reasonable" functions it'll work fine with riemann though
Oh it might still not be Riemann integrable
right
even in the lebesgue situation, you can have a 2-d measurable function which has some 1-d slices that aren't 1-d measurable or are measurable but integrate to infinity
Ok suppose you had a function that was Riemann double-integrable in the sense that this is well defined (has the same value for any partitioning)
but if the 2-d function is absolutely integrable, such badness only occurs on a set of measure zero so it's fine
Then you can equate it to its iterated integral version?
(that's also part of the fubini theorem)
hmm, if it's absolutely riemann double-integrable then it's also absolutely lebesgue double-integrable, so you can definitely do the iterated thing and the results will be equal if you're using lebesgue 1-d integrals
Right because on the individual measure they’re non-zero but from the perspective of the product measure it’s 0
i bet there are degenerate situations where the riemann 1-d integrals can still be problematic though
but offhand i'm not sure
yea imagine a function of 2 variables that's zero everywhere except along the x axis, where you make it the characteristic function of some 1-d nonmeasurable set
If it’s Riemann double integrable then surely each part is also Riemann integrable?
Otherwise it wouldn’t equal for any partitioning no?
check this
so things can get screwed up in either direction
iterated integrals ok but double integral not ok
or
double integral ok but iterated integrals not ok
yet another example of why the riemann integral sucks haha
fo sho
Ok so this is not true
Oooh
Perhaps it’s because it’s just the partitioning of areas
Not individual partitioning of each dimension
even the statement of fubini is a mess when you're using riemann integrals, check this as well
It seems they can’t swap the order here either?
not automatically, you need stronger hypotheses
It’s just saying the integral of the 2nd part of Q exists
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yeah so that's one vector parallel to the plane, now just use the direction vector of the line (i.e. <1, 2, -3> for the second and take their cross product)
then what do i do with the normal?
you can write an equation of a plane using any normal and any point in the plane
and that would be the answer?
so the logic is that if you think of any vector formed by some point P_0 in the plane and any other point P in the plane, the vector formed by those 2 points would be perpendicualr to a normal vector right?
so dot product between a normal and vector from P_0 to P would = 0, this can be used to write an equation
notice how the vector (x - x_0, y - y_0, z_z_0) is just a vector between two points in the plane (x, y, z) and (x_0, y_0, z_0) and then that equation is just writing a dot product that equals 0
with the normal vector (a, b, c)
im too lazy to do actual calculations, but as long as you understand the concepts im sure its fine 😄
so basically i just cross producted 2 direction vectors to get the normal then used point P to create the vector equation would that be right?
yeah basically if you have any 2 vectors that are parallel to the plane you can get then a normal
as long as they arent colinear
and from that just use that equation of the plane, its easy to remember if you understand intuitively that its basically a dot product set equal to 0
@chilly ermine Has your question been resolved?
alr thanks
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Prove that the set of the real numbers is not bounded inferiorly using the definition of infimum, axiom of completeness, and other theorems.
It is of real analysis or mathematical thinking
aoc is an axiom of ℝ
@dusk hound Has your question been resolved?
What is aoc?
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Hello. Can I get a hint on where to start from with this one? I can't think of a simple way to simplify it...
Find all such values of a, for each of which the inequality is true for all real values of x.
um so let y=x(a-cos2x)
so in terms of bounds on y, when is sin(y) between -1 and 1 inclusive?
I honestly feel dumb rn. I can only think of when |x| <= 1/|(a-cos2x)|...
or well, if something equals zero
think about possible inputs and outputs of the sin function
you can stick anything in, but you only ever get values out between -1 and 1 (inclusive)
true..
sin(theta) represents values of y coordinates of points on the unit circle
so they can only be between -1 and 1
so the output of that expression in the middle is always going to satisfy the inequalities...the only other potential problems would be if something is undefined for a subset of the real numbers, but there's no division by 0, no functions with domain restrictions etc. so the inequality just holds for all real numbers
and for all values of a
looking at the function, it gets out of the restricted boundaries pretty quickly...
and the suitable values of a seem to be around [-1.4; 0]
ouch
okay, I got it right this time...
the answer
And I still don't understand how to get it..
I guess I might have made the right point though.. I'll try to solve it this way and see if I can get something interesting..
wait, what would I even get from that?..
..
@storm saffron Has your question been resolved?
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"True or False: If A is a positive definite matrix, then A^3 is a positive definite matrix"
I'm not exactly sure how to approach this
how do matrix operations affect its positive definiteness (or whatever the word is supposed to be)
do you have a characterization of positive definiteness in terms of eigenvalues?
a theorem that tells you "a symmetric matrix is positive definite if and only if..."
I have the following
"A self-adjoint matrix A: V->V is called positive definite if <Av, v> > 0 for all v =/= 0 (v vector =/= 0 vector)"
What can you say about the eigenvalues of such a matrix
its not an observation I made but I believe our instructor said something like, the eigenvalues will be greater than zero
and if positive semi-definite, then the eigenvalues are >= 0
ok
suppose the eigenvalues of A are all positive
what can you say about the eigenvalues of A^3?
im not sure,
How do A and A^3 relate to each other
i know its the same matrix A but just with a different power
well one way to find out is to diagonalize A
diagonalizing A to obtain SDS^-1 representation and then taking D^n (in this case D^3) ?
yep
hmm
A^3 will be S(D^3)S^-1
but then in that case D^3 is just the eigenvalues cubed
wait no
im dumb
uhh
wait no im right
result is a positive number
T
T
T
$\top$
yes
but i think i can use what we just did
Philka
Obviously
yea use the same type of argument
so lemme just make sure i got this right
negative definite means every single eigenvalue is strictly negative
yes
A^8 thus cannot be negative definite because its an even power
strictly greater than 0
so if we had negative semi-definite A, A^8 could only guarantee positive semi-definite but not necessarily positive definite
yep that's right
semi-definite but not definite means zero is an eigenvalue
and zero will still be an eigenvalue if you take powers of A
it has to be an eigenvalue of the matrix, if its semi-definite?
like if we know A is semi definite
if it's semi-definite and not definite then yes
then at least one eigenvalue is necessarily zero?
or i guess, not at least one, but one
at least one if you count repetitions
in the extreme case you have the zero matrix
but zero matrix has no eigenvalues right
oh ok
(it's diagonal, so the eigenvalues are on the diagonal)
sounds good. i might be back for more questions cuz my assignments are brutal 💀
But i super appreciate you breaking down the steps to answer this T/F man
sure, if you get stuck or want to check your answers, just open a new channel
cheers
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Actually, I'm back 💀
I just wanted to check how can we know A is diagonalizable
it's symmetric, right?
hmm
the definition includes self-adjoint matrices and, those are symmetric if real entries
ah yea good
self-adjoint if complex
symmetric if real
then the spectral theorem tells you that it's diagonalizable
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hello
we have the following problem:
f:R\ {0} -> R , f(x) = (x+2)e^{1/x} . the equation of the oblique asimptote to +infinite is:?
so first we have to find m
which is defined by this:
which is 1
<@&286206848099549185>
now i have to calculate the n
which is defined by this
bcz y = mx+n
asimptote
but i dont know how to calculate this
e^1/x is 1
x+2 - x as x -> inf is theoretically 2
right?
so the final answer 2?
so y = x + 2?
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Can someone walk me thru how to get angle theta?
you can get BC with cos theorem
AB and AC with pythagor theorem
finally cos theorem again for the theta angle after you get all the required sides
okk tyy
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perhaps the slopes are the same at different places
what are "both" tangent lines. Is is asking for the equation of the tangent line at t=pi/6 and t=5pi/6
Then, they may have the same slope
no, because the y-intercepts may be different
you must compute that using point-slope form, etc.
the point of intersection?
no, because the tangent lines may not go through that point? I don't know where on the graph it is at t=pi/6 or 5pi/6
you need a point on the tangent line. Plug t=pi/6 into (x(t), y(t)) to get a point on the tangent line at t=pi/6
oh are you trying to find the slope of the tangent lines at the intersection?
Then yes, 1,1 works
the slopes should be different okay I understand
those are the wrong numbers for t I believe
t should be like pi/2 and 3pi/2
well, you can check that 3pi/2 works
manually
right
i basically just solved for x(t)=1
yes
did that work?
no
if I plug 1,1 into the second equation it doesn;t work
oh its probably a type
typo
it should be y=-2x+3
that sounds about righr
that seems right
You too!
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bro you're back again 💀
lmaooo
the first bounds are from pi/2 to 5pi/6
the second are from 5pi/6 to pi
yes, I think so
its pretty easy to botch these integrals so you can probably just check on wolfram or something
yes, I'm afraid I primarily do algebra and the consistency of my integrals is in question
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yo
I was just studying about transforming from Cartesian coordinations to spherical coordinations
and between my notes i found this law :
$\frac{d\vec{U}{\phi}}{dt} = \frac{\partial \vec{U}{\phi}}{\partial \phi} \frac{\partial \phi}{\partial t} + \frac{\partial \vec{U}_{\phi}}{\partial \theta} \frac{\partial \theta}{\partial t}$
mino
can someone tell me the name of it so that i can look for it more ?
chain rule?
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im stuck at findind d and b
i just want the values that make the function continuous
Do you know how to find the values?
yes and for them to be continuous they need to be equal
so find the values that make the limits equal
so after finding the limits make them equal to each other
You can also just find the value that makes the equations equal exactly at the point where they connect
and solve yeah
so what happens to the x in there
i subsitute the x at where they meet right
kindly try it out please im stuck at b -d = 2
i cant move forward
<@&286206848099549185> please
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no
@patent quail Has your question been resolved?
no
<@&286206848099549185> please take a look at this problem
Ok sorry
@patent quail I was at church so I had to stop so
can you show you work
Ohhhh I see where
The full function is continuous
so you can find b by finding where it is continuous with y=2
does that make sense
So find b first with the other equation
not really
i got a to be 2 and c to be 2 but for b and d all i have is a relation
b-d = 2
The reason you ended up with this equation was because
There are multiple b and d that will make it continuous
To find the b value, we need to have an “anchor”
so instead of comparing it with another unknown equation find the value of b that is continuous with y=2 (the other equation next to it)
oh I see why it’s weird…
I think finding d and b is related to the mean value theorem which I don’t know @patent quail
forget the mean value
lets just deal with the one that makes the function continuous
oh okay
try it out yourself
i already did
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I think you need to apply mean value theorem
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Can someone help me with question 33 and 34
show us ur work
Im trying to work out the questions with variables but it asks the verify the identity for the thinks so idk
Do I just work it out with the variables?
yes
That would actually kill me 💀
i mean, not a lot of work
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can anyone convert this into a cosh function
a would be the lowest point above x axis
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What do you do when the number is below the variable?
so here:
tan55 = a/6
we know what to do: 5 * tan55 = a
but then in this example:
tan40 = 12/a, how do I find a?
@lunar nacelle
wrong ping lol
u have to do the opposite operation of what has been done to solve for the variable
uh....
water beam
tan40 * 2 is..
huh?
where are you getting 2 from
it's a mistake I meant 12
you divide both sides by 3
we arent doing tan40 * 12 and dont use the decimal value
using exact values
keep it as tan40
so what do I do ?
no...
what am I doing wrong?
$\frac{3x}{3}=\frac{1}{3}$
water beam
none of what you wrote here is right
This pre-algebra video tutorial explains how to solve basic equations by using addition, subtraction, multiplication, and division. Some examples can fractions. You can cross multiply any time there are two fractions separated by an equal. This video also contains practice problems of solving multistep linear equations.
Algebra For Beginners...
watch this video
just like he says at 5:40, same method
no its not the same thing as what ur doing
you are saying 3 times 1 is 1
and 3 * 3x = 1x
you are dividing both sides of the equation by 3
tan40 = 12/a
so we divide both sides by the upper number? (12)
10 = 12x
x = 1.2 ?
i dont think you understand what youre doing here, you are getting all these random numbers from nowhere
i suggest you watch the video in full
a is 12
alpha is 40
I need to solve for b
and you wont be able to solve for b if you dont know the general approach to these types of questions
like i said watch the video
once you have watched the video
come back to this question
and see if you can do it
I think I've got it
tell me
something like this then? (
not quite
$\tan40=\frac{12}{a}$ yes?
water beam
yep ^
you want to solve for a yes?
I want to solve for a
water beam
I get
a * tan40 = a* 12/a
does this line make sense to you?
this is what happens if you times both sides by a
got it 👍
yes
so we got
a * tan40 = 12 * a
you just told me 12a/a is 12 simplified
how can there be another a next to the twelve
one second..
so on the right side we have
12/a * a
do you understand the fact that $\frac{a}{a}=1$
but that just turns out to be 12/a
water beam
if you have 2 apples and share it among two friends, how many apples does each person get?
a gets cancelled out
oh--- because no matter what it is, If it's divided by itself it'll always be 1
Yes
ok ok
We do
it is the same thing
12*a is 12a
$\frac{12}{a}\cdot a=\frac{12a}{a}$
water beam
still don't get it
what do you not understand here?
You have multiplied 12 and a in the numerator
a is like x?
ok so
12/x = 12x/x * x
why are you changing a to x?
you are overcomplicating everything
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so we just temporarily take 12 out
this may help you with the basics
because it seems you are missing a lot of basic knowledge here to solve equations
Is this correct tho?
and so we got:
a * tan40 = 12/1
yes and 12/1 = 12
water beam
what happens to tan40/tan40
it became 1
so
1 = 12 / tan40
a * tan40 is 1
so we are left with:
1/tan40 = 12/tan40
you cannot simply ignore the fact that the a exists
right?
I'm not ignoring it, But a * tan40 is just.. tan40
cuz u said a is 1 when divided...
are you going to listen
a/a = 1
any number divided by the same number
will be 1
it doesnt matter if its 90000000/90000000
or 20000000000239493/20000000000239493
it will still be 1
do you understand yes or no
yes
1
water beam
so
a = 12/tan40
yes
put that into calculator or whatever yes
https://youtu.be/4CKDqvddhhg?si=66zT8ATm72MQpXrR
you should rlly watch this and some other videos on algebra
Welcome to How to Simplify Fractions (Part 1) with Mr. J! Need help simplifying fractions (aka putting fractions in lowest terms)? You're in the right place!
Whether you're just starting out, or need a quick refresher, this is the video for you if you're looking for help with how to simplify fractions. Mr. J will go through simplifying fraction...
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