#help-36
1 messages · Page 105 of 1
Well it’s simpler to multiply one equation
how is it still correct?
The equation is still correct as long as you do the same operation to both sides
wdym
when you multiplied the equation by 4, you did it to the left and right side because that would keep the equation equal
yes i know that
But i only multiplied on the
I
not the II
why is it still correct?
hmmm why should it not be correct
The equations are not equal
I know why you’re asking it’s hard to explain maybe someone with better terminology can explain it
But can you explain why we would need to do the same operation to the first equation
It is still “correct” because the second equation is equal to itself after it was multiplied
if you have a system of 2 equations
If you graphed the equation before and after you multiplied they are still the same line
hmm i see
you can subtract one from the other and the resulting equation has equivalent information to the equations you got it from
and since you can subtract one from the other an arbitrary number of times
So the intersect of the X and y will stay the same since the lines did not change
even a non integer number of times
you can just take equation I and subtract 4 times equation II from it
and the information about the system won't be lost
the proportion of the equation is the same as long as you multiply to both sides
Not sure what you meant by proportion but maybe that helps
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Hello I have a question about transformation rules for a value
does it works vertical stretch by a factor ½ or stays a factor by 2 if we have a 2 in a?
or does it only works for k value
$$y=-2(x-3)^4+5$$
アキラ (>_<)
here's the actual function but im just wondering about a
I keep forgetting if it's factor by -½ or just factor by -2
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dumb question but why are there 3 solutions instead of 2, and why is it not just pi/6 and pi/2
my teacher said its bc it goes around the unit circle more times but i dont get what that means?
so if its any trig function where x has a coefficient > 1 does the coefficient determine the amount of solutions
yes, if you have a coefficient of y then the new period is 2π/y
in this case the coefficient is 3, so the period is 2π/3
so π/6 is a solution, but so is (π/6)+(2π/3) = 5π/6
ohhh
so if i got a question like this the last box would be all the solutions? bc the period is pi/3 instead of pi
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can someone help me understand how to factor this
x^4 + x^3 + 2x^2 + 4x -8
i would first try to plug in some low numbers like
-2, -1, 0, 1, 2
and see if any of those give you 0
1 does
sure
since 1 is a zero, the polynomial you have has a factor of (x-1)
so you would divide the polynomial by (x-1)
okay got that
that just blew my mind
the plugging in numbers part
cause i was doing synthetic division and its the exact same thing 1 is a zero
so okay whats next
do i just group the rest
well after you divide it out you should be left with a cubic equation
once again
plug in some numbers
to see if any are roots
the factoring by grouping doesnt work
ok ill suggest you try plugging in some values for x again
okay
it is + 8 at end
ik i tried it
so generally use -2 , -1, 0 ,1, 2?
yes
why is that?
Because teachers maybe give us equations that have simple roots to simple our life
not "generally"
1 and -1 are always good idea to try but there is specific reason why 2 and -2 are good idea in this case
In school i mean
still no
then how can u tell how to pick which numbers are good without going through it all
in general what u try is number of this form
like how did u determing that 2 and -2 is good
yeah im doing this
so
because ur last number is 8
it would be good idea to try -8, -4, -2, -1, 1, 2, 4, 8
(but you start with -2, -1, 1, 2 since these numbers are easier to try)
im at the part where u factor it cause i just did 1 and i got a zero then i got
x^4+x^3 + 2x^2 +4x - 8
so in my notes the -2 did get a 0
but after it it goes to 1
then it also goes to zero
is correct
how come -1 wasnt tried
im just unsure how it went from -2 to 1 (maybe my teacher did try to do -1 but i did not write it down
see
wdym
is this why or is there some skill that helps you determine what numbers are good
not rly
i assume they either knew the answer beforehand or just mentally checked
(mentally checking becomes a quick process after some practice or time doing math i guess)
ye ur teacher did it twice
until it becomes standard form
the ax^2 + bx + c is that right>?
idk what u r referring to
this last part of synth.
ur teacher just divided the original polynomial by (x + 2), then divided that result by (x - 1)
if that's what ur talking about then ig answer is "yes"
the 1 0 4
if i write it out it would become x^2 +x +4
👍
why do u not write it out?
write what out
the 0x\
ic, so its 0 so dont bother
after u get x^2 + 0x + 4. u r done because this expression cannot be factored
therefore there is no further need to apply synthetic division and you can remove the 0
if u needed to apply division again then u can keep the 0
you stop doing synthetic when u can factor the expression?
like how x^2 + 4 is finally factorable in this last part
u stop when the end result is no longer factorable
x^2 + 4 is the last thing u get after using division, and it cannot be factored
ok my b only x^2 - 4 is factorable
ye
u can think of it as
x^2 + 4 is always above the x-axis
because u r taking x^2 and moving it up by 4
so it has no real roots and can't be factored using real numbers
u mean no zeroes cause it has to be on x axis?
does it have to be on the x axis to have zeroes?
is this a valid statement ^
for purposes of an introductory alg class, a polynomial has a zeroes where it touches the x-axis
safe to say for pre calc too>
?
i dont think we have that part yet in the semester
but good to know this either way
@tawny halo @vital surge ok thank you for your help, i understand now. have a good day, im gonna study graphing rational functions now and ill come ask again here hope u guys can help again.
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I was thinking it would be a set of sequences of length z? from 1 to n?
or is there a easier more mathematical way of putting it
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is there an easier way to do this
easier way would be to just kinda list them out
cuz in test i only have like 15 mins to complete the non calc
o
so like
trial and error?
or like
the triangle
essentially? triangle is quick
you can also skip writing out some steps once you've practiced this sort of thing
like a lot of the factorial stuff
ohh ok thanks
i dont understand
what this means
oh
do the brackets mean
cobination
combination
nCk
yes
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✅
Yes
oh naurrrrrrrrrrrrrrrrrrrrrrrr
do u think
its worth 5 marks
because i havent started the chapter yet
and my test is tomorrow
on last years test it had one question on the pigeon hole principle
and it was only 2 marks
this is too complicated
Say we have a two digits number. What is the maximum sum of the digits?
if the max sum is 18 and u have 19 numbers
that means tehre is one that is repeated?
Yes 🙂
Yes, it all comes down to you "running out of possibilities". Like here we have 19 numbers, but 18 possible sums of digits
how come
this one is different
why did they remove one from each pigeon hole
Here they firstly want to determine the number of crayons you can have at maximum without the condition being wrong
So you can have 1 green less and 1 red less than asked for
oh
so there is a definiute chance of at least 6 red or 5 green
if we put some in
when theres 5 red or 4 green
because minimum being is like 1
crayon
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How do I answer this?
Do you know that the definite integral between a and b of a function gives you the area under the curve between a and b for that function?
Oh I figured it out thank you
Area is always positive
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Hello! I have to find the first four nonzero terms in the Maclaurin Series of $f(x) = \frac{2x}{1+x^2}$
dabbingpotato
It seems pretty impossible to brute force it and i'm pretty sure theres a neat little trick thats supposed to be used. Could anyone enlighten me?
note that this is the derivative of ln(1+x^2)
Okay so we just do the maclaurin for ln(x) and then substitute the terms with x for 1+x^2 and then take the derivative?
yes
okay thanks :D
ohhh
then differentiate, yes
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This is what I did so far
I’m so lost when trying to find yp
Idek if I found the unprimed yp correctly
The Ax + B + Ex^x
Ee^x ****
If someone could help me I would appreciate it
Btw it’s method of undetermined coefficients
<@&286206848099549185>
<@&286206848099549185>
<@&286206848099549185>
sorry, im not a ready
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wait so please do not give me the answer
or any sort of hint
so
the question asks me to find the parabola that shows the shape of this cable
so
to find the equation of a parabola
we can either have 2 points: vertex and any other point
OR
3 different coordinates
so uh
i think i can identify two points right now
one is y-intercept which is
(0, 75)
the other is (180, 75)
i cant seem to identify the third coordinate
am i on the right track anyway?
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oh wait
oo
isnt it literally just
(5, 3)
(6, 9)
(5, 13)
so t = hours = x-axis
r = rate of rainfall in mm = y-axis
yup
easy lol
now just 3 equations
simultaneous equations
woo!
@oblique mica is there a way to like identify which equation goes with which
in terms of simultaneous equation
my 3 equations are
$3=9a+3b+c \ 9=36a+6b+c \ 13=25a+5b+c$
pixel
what do you mean
also your first point should be (3,5)
your points are just backward in general
wym
ohh right right
i even draw a diagram to do that
but silly me wrote the wrong coordinates
💀
this is really helpful because you get two different x values that equal the same y value
you can find the axis of symmetry that way
wait
hold on
my coordinates should be
(5,3)
(9, 6)
(13, 5)
(t, r)
right
which two different x values have the same y value
they're all different
oh yeah
you cant do the axis of symmetry thing then
so if you have a set of equations and you want to do elimination, you want to eliminate a variable from two equations using one equation
that probably doesnt really make sense, so let me make an example
4 = 3a + 7b + 3c
6 = 2a + 5b + 3c
7 = a + 4b + 5c
you can eliminate the a in the top two equations using multiples of the bottom equation
you would get
-17 = -5b -12c
-8 = -3b -7c
then you would do the same thing you did as before
@steel kite Has your question been resolved?
oh yeah im so sorry i solved it
im now on similar questions
except i have coordinate
which is easy
thank you for your help
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can someone help me with upper and lower bounds theorem
basically, the statement says
if we divide p(x) by x-b with (b>0) using synethtic division and if the row that contains the quotient and remainder has no negative entry, then b is an upper bound
and if we divide p(x) by x-a with (a<0) using synt. divison and if the row that contains the quotient and reminder has entries that are alternately nonpositive or nonnegative then a is a lower bound for zeros of p
well in this example i got im left with
2 10 14 6 0
in a synthetic divison
this is quotient and remainder
so this has no negative things
oh okay wait
okay i got it
i was gonna say why is it upper bc it has negative and it also could be lower but i divided it by 3/2 soo its upper
anyway lol im closing the chat
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ive substitued it in and like
it does equal 1
but i dont understand how to find the point that is missing
What did you sub
well
by elimination
doesnt it mean i just do
x^2+y^2
and like
put the t values in
well anyways when i did it and simplify it all you end up w (t^2+1)^2/(t^2+1)^2
which is equal to one
but i dont get how to find the missing point
consider the range of x
doing long division on (t^2-1)/(t^2+1) may make the missing value clearer
doing long division on (t^2-1)/(t^2+1) may make the missing value clearer
have you ever done polynomial long division before?
i thought it just equals to 1 no?
wiat
ohhh
wait no 1 was for the big one
ok lemme try
oh ok
so i got
the remainder as -2
and the quotient is 1
yes, so
$$x = 1 - \frac{2}{t^2 + 1}$$
ℝαμΩℕωⅤ
can you now see what value(s) x can't attain
wait how did u do that?
do what
wait oh i get it
that's what the result of long division gets you
think for a few minutes
yes, x can't be 1
and then what does
y =
do i just like
use
x^2 + y^2 =1
and of x cannot be 1
then y cannot be 0?
hi
i have a bit of a question
why cant y not equal to 0?
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hii, got a question about an induction case in n^k < 2^n where i've defined n = k^2 + 1
i want to make induction for this term, but i need to factor out (k^2 + 1)^k in my right side, and idk how
this
if i can factor out that, i can remove the factors out, and just reapply induction on the factors that has left
this is my hypothesis
thats why i need in the right side (k^2 +1)^k as a factor in the right side
any help on the way to factor out this crap? 😦
oh btw it was the left side XDD
not the right
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I've made these two equations both equal y^2, now I need to solve them simultaneously, how would I go about doing this? It's getting late and I've been doing this all day, I don't have it left in me to figure this out myself lol
also in second equation u could take square root on both sides and substitute the value of y into first
get value of x and then use that value of x to get y
I don't have the value of y
ohhhhhh
silly me
they equal the same
right, that is why I just did all of that
there is a y in the first equation
that would lead u no where
wdym?
$$-(x^2 + 15 - y(8.5)) = (\frac{(x+0.5)(x)(x-0.43)}{0.4}+5)$$
JustToPro
u still have both x and y in there
what i would do is like i did in the picture
$$(\frac{(x+0.5)(x)(x-0.43)}{0.4}+5)^2 = y^2$$
square root both sides
$$(\frac{(x+0.5)(x)(x-0.43)}{0.4}+5) = y$$
JustToPro
yeah, that is what I had earlier, but that equation (cubic polynomial) does not equal the other equation
what u mean?
I am trying to get both equations to equal each other, so that I can solve them simultaneously
ik
the first equation equals y^2
but that second equation does not
thats 1 of the methods known as substitution method
where u substitute the value of 1 variable into the other equation
ohhhh
I substitute that whole equation into every other y in the first one
ok, that is going to be extremely confusing but I can do it
I will report back in a few minutes
ok
ah, this is awkward
your little substitution trick has just invalidated all the math work I've done today
eh, its fine
can u show ur question?
maybe there is a simpler way ( i doubt there is tho)
well the equation I started with has 1 Y in it
there isn't really a question, I am trying to find where two relationships intercept
it's for an assignment, but it doesn't explicitly tell you to do it
oh ok
which equation is that?
the one below?
that top equation is the circle
and so is the 2nd one in that most recent image
just I spent all of today trying to make it equal Y
im confused btw , the recent image is that ur original equation which u transformed into the old image (the one u posted first)?
no, old image came first
ok, let me organize my thoughts
this was the circle
but I turned it into this to try to make it equal y
that is the exact same equation
this is a cubic polynomial
I am trying to solve for X
because X is where they intercept
why is the circle like pac man?
doesn't matter
it's two functions
the mouth is an inverse reciprocal
would I be able to just find the square root of both sides to get rid of the brackets?
JustToPro
so how would i remove the brackets on the left?
would I have to expand them?
because that is going to take a very long time
yeah i dont see another way
ugh, ok
\left(\left(x+0.5\right)\left(x\right)\left(x-0.43\right)+0.75\right)^{2}
oh
where did the 0.4 go from the denominator ?
can't even put it in here
use dollar signs
I just got rid of it to make it easier
$\left(\left(x+0.5\right)\left(x\right)\left(x-0.43\right)+0.75\right)^{2}$
JustToPro
I was hoping to put it here because I don't have anywhere to write this out while expanding it
well u got rid of it wrong way
no I mean I literally got rid of it
oh like u skipped it?
I made these equations to begin with
if I was smart I would have made it a quadratic
btw what u would get is a 6th polynomial equation which u would have to solve
ah man
idk how to solve 1 of those
you know what, I am just going to make it easier and get a lower mark
but actually a higher mark cause I can do it
thanks for the help anyway, I've learnt some stuff even if I can't use it
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You can use the vector equation of a line
Assume the parameter as lambda or smth
And you know the distance CD, so use the distance formula to find possible values of lambda
D can be lying between B and C or outside B and C right
wait i draw
so i can take vector direction of BC x 6/12 right
You mean unit vector?
why cant i juz do this
i still get the wrong answer
I don't get which vector you're multiplying with 6/12
according to here, BC direction vector is (12,-6, 12)
so if i take this BC direction vector multiply by 6/12, wont i get BD direction vector?
BC length is 18 though
So divide by 18 to find unit vector
And then multiply with 6
o-
Yeah
BC divide 18 times 6
Np
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how is the blue part true?
Why do you think it's false?
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Someone told me that having delta <1 is a stricter bound than being >0, so that for this specific problem the inequality being true for delta <1 means it should automatically hold true for all delta >0, and by extension all epsilon >0. Is this correct, and if so, how do I describe it in the informal proof?
@hexed bison Has your question been resolved?
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Maybe I should post it here too:
Is that proof missing some steps or would you say it's good?
hm it's an interesting approach
arguing via the availability of pivots
we proved it in a completely different way :D
have you been taught the elimination/division manipulation before
or rather are you allowed to use them?
if so then I'd say yes, not sure if it doesn't cover edge cases
the common approach is to say that if the only solution is the zero vector, then ker(A) is {O_n} and from that follows Injectivity
because if any two vectors would then be mapped onto the same vector
due to linearity dim(ker(A)) would have to be > 0
which would defy injectivity
Would you say it's missing some steps?
Or is it a fine proof
oh
I'd put it slightly more explicitly
Why does from "we can manipulate A into the unit matrix" follow "A is invertible"
and also
Why are there no "free variables" if A has a single solution
Well if there were, then we'd have infinitely many solutions
So I'd write it down like that?
Hm maybe more like "Since the H.S. of A has only the zero-solution, there are no zero-rows if A is in RREF form."
which you can then use to express that there are no variables in the set of solutions
Alright, thanks
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It says not all series will need the nth term test, does that apply for #1? Can I assume its divergent?
you can apply the nth term test here, although there should be more justification
I could, but is it really necessary to add up 6/7 +7/12 +8/17+9/22?
Sounds like a quagmire
the nth term test says that a series diverges if its associated sequence doesn't converge to 0
Yea so i have to find the sum right
Or is there another way??
that's not what the nth term test asks for
it's not the sequence of partial sums, just the sequence of terms
What does that even mean?
Terms of what?
So i just find the limit of (n+5)/(5n+2) as it goes to infinity, and if its not 0 then it diverges?
yes
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@heavy laurel Has your question been resolved?
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I think you would have better luck asking it in the appropriate early-uni/advanced-math channel.
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struggling a bit with this optimzation problem
I formulated $L(x) = \sqrt{x^2+36}+\sqrt{(20-x)^2+196}$
The Great D
and after differentiating I find its minimum at x=6
but the book says the correct answer is 5.71
Did i construct a wrong expression for L(x)?
Looks good to me idk
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what is your justification that this equality is true?
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my answer is wrong, where did I go wrong?
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Just use Newton’s third law of motion
Remember n! is defined $$1 \cdot 2 \cdot 3 \cdot ... \cdot (n-1) \cdot n$$
haha i wish i could
ohh so do i think of it as a number
Good
Kind of.
$$\frac{n!}{(n-1)!}$$ $$=\frac{1 \cdot 2 \cdot 3 \cdot ... \cdot (n-1) \cdot n}{1 \cdot 2 \cdot 3 \cdot ... \cdot (n-1)}$$
Good
ohh thank you so much
Welcome.
that looked like a nightmare to type 😭
🤗
just curious how do you know when to stop though
like when do i stop subtracting 1
Could you give more information? I'm kind of not following. Do you mean when do one stop to type numbers until it reaches n, or n-1?
cause you know for factorials its like in decreasing order e.g 7! is 7 times 6 times 5 times 4... 1
how do i know when to stop for n
it's still down to 1... n is just some integer
$1 \cdot 2 \cdot 3 \cdot ... \cdot (n-1) \cdot n = n \cdot (n-1) \cdot (n-2) \cdot ... \cdot 3 \cdot 2 \cdot 1$
Good
thank you as well!
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how do we perfect square this
when the third is negative
What do you mean by "perfect square" ?
how do make it ( )^2
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how do i find the kernel and range of this?
diff channel pls
Ok
For the kernel, you wanna find the matrices M such that T(M) = 0
when c and b =0 then ?
The range, basically what each of the outputs "look like"
Yep, all matrices $\pmqty{a & b \ c & d}$ with $b = c = 0$, so stuff that looks like $\pmqty{a & 0 \ 0 & d}$
@tulip coyote
here @fiery trail
ook
how do i express all those possible matrices?
like
will it be a matrix with variables
You can, you could leave them as per how I did, or you can split that matrix into linear combinations of linearly independent matrices and say the kernel is spanned by those
Hopefully it's clear how you could break down that $\pmqty{a & 0 \ 0 & d}$
@tulip coyote
and what would the range be for this question?
can i say $\pmqty{a & 0 \ 0 & d}$ , a,d in R?
risa★
two \
risa★
risa★
And yea, that should be fine, or you could also notice that
[
\pmqty{a & 0 \ 0 & d} = a\pmqty{1 & 0 \ 0 & 0} + d\pmqty{0 & 0 \ 0 & 1}
]
so the latter two matrices span the kernel
@tulip coyote
yes
It's a similar idea for the image, you can either say it's all the matrices of the form $\pmqty{3c & 0 \ 0 & 2b}$ for $b, c\in \bR$, or you can similarly split up that matrix if you want
@tulip coyote
(it's worth also noticing that the kernel has dimension 2, the image also has dimension 2, and as a real vector space, the 2x2 real matrices have dimension 4, so that's all great when it comes to rank-nullity)
for kernel we were looking for matrices M such that T(M) = 0, but whats the range basically?
Everything that you can "get out of" T, what all the outputs of T look like
im just confused cuz the $\pmqty{3c & 0 \ 0 & 2b}$ is just the question
risa★
Do they ask you to represent the range in a particular way or anything for the question?
they didnt specify
for example this one was in the form of a quadratic
both the kernel and range
as the answer
but i dont think u can rly do taht for the matrix?
a quadratic for the range of that one?
And for the matrix, you can give them as matrices (in fact, the kernel is the same space as the image here(!))
oops sorry, it was proven using a quadratic but the answer was "any polynomial in R^2"
FOR KERNEL
oops
wait
Ohhhh I was gonna say 
kernel = {c(x-5)(x-7) | c in R}
Ah, I see, yea, cause 5 and 7 would be roots of your polynomial so (x - 5) and (x - 7) are factors
okk, wait but kernel was (a 0 0 b) and range was (3c 0 0 2b) tho?
Yep, but like you can replace the $3c$ with another variable, as with the $2b$, so you see that all the matrices are gonna look like something like $\pmqty{x & 0 \ 0 & y}$ with some real $x,y$
@tulip coyote
Which matches with what the kernel looks like 
okk i get it!
Perfect 
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for this theorem isnt it also necessarily that vectors must not be the zero vector?
if one of them is the zero vector, then there will be a nontrivial solution
you don't need to make a special exception for that case
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i despise these problems
@tawdry minnow Has your question been resolved?
Let x * y = f(x, y) and x + y = g(x, y)
Now we have f(7, 3) = 158, g(3, 9) = 45, g(f(2, 3), 4) = 377
Now you can see that this is clearly not nearly enough information to peg down the general form of f(x, y) or g(x, y). We have no restrictions on these functions at all. Are they commutative? Are they even continuous?
All we have is that a finite number of points have been defined. Functions from R^2 -> R have cardinality of (R^2)^R = R^R = beth_2. That's a lot of possible functions to choose from.
@tawdry minnow ^
I mean, ok
That answers nothing and doesn't narrow it down at all
Now we are getting somewhere.
We have a model.
Sorta
There are still infinite solutions
But we managed to reduce the size of the infinity
From beth_2 to beth_1
So he said it's a binomial, I suppose both f and g, which means that it's two terms.
this sounds like overanalysis
Not really overanalyzing, because I'm not really analyzing it at all, just explaining why it's a broken question
the way these questions work is that ur given some numbers & symbols denoting obscure operations with the goal of figuring out what those operations are
there's plenty of these online and this problem is just another one of those
it's true there's "infinitely many solutions" or smth similar but the creators usually intend for there to be one reasonable way to proceed
... not that i have a high opinion of this kind of question, but i wouldn't say it's inherently broken
it's just pure guesswork ig
Well, even if we assume that this is as simple as f = ax + by and g = cx + dy we still have one too few equations to determine the coefficients.
,w Solve[{7a + 3b == 158, 3c + 9d == 45, (2a + 3b)c + 4d == 377, 3a + 2b == 8.5, 4c + 5d == 20.5}, {a,b,c,d}]
(i assume) that's enough info to find both functions
So the model is more complicated than ax + by
It's not, I can find many different solutions. The problem is finding the intended solution.
which makes it tricky
I mean... tricky is not the word I would use.
But sure
Let's change the model to something more complicated: ax + by + c that's 6 unknowns
Total
that third line is correct right
,w Solve[{7a + 3b + e == 158, 3c + 9d + f == 45, (2a + 3b + e)c + 4d + f == 377, 3a + 2b + e == 8.5, 4c + 5d + f== 20.5}, {a,b,c,d, e, f}]
Pick any value for a.
And the rest of the values are determined.
Except for a = 123/4, apparently
c(ax + by + e) + dy + f, where a is a free variable not equal to 123/4, and b, c, d, e, and f are defined as above.
Simplification left as an exercise to the reader.
Or hell, I'll type it in to WA and get it to do it.
,w simplify 2901/(1230 - 40a) * (ax + (299/2 - 4a)y + 5a - 581/2) + (8259 - 245a)y/(1230-40a) + (27684-405a)/(40a - 1230)
Any value of a that you select will make the function hold
And of course, you can have more complicated models, like quadratic models
Oh sorry my bad
That's (x * y) + y
Not (x + y) * y
,w simplify a * (2901x/(1230 - 40a) + (8259 - 245a)y/(1230-40a) + (27684-405a)/(40a - 1230)) + (299/2 - 4a) y + 5a - 581/2
@tawdry minnow ^
Generally, there's some "clever trick" that the person posing the question thinks is obvious, but the puzzle is typically utterly lacking in conveyance.
@tawdry minnow Has your question been resolved?
the fu is this
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I’m having trouble proving this, I’m trying to do something with x*m_2 = m_1 but I can’t get a rigorous argument
yep that's it
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anyone able to do this?
sure
consider the region in the first quadrant bounded by the graphs of y = x^2, y = 1, and x = 0. Use the shell method to calculate the volume of the solid formed by revolving this region about the line y = 2
umm
just encase it's hard to see
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Not sure where to go from here
bingo
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I tried putting it in the calculator and all that fun stuff. I’m guessing it’s pretty simple but I have no idea what to do 😭
like in the calculator?
calc is not required

