#help-0
1 messages · Page 583 of 1
yes
ohhh ok
bunny
I think so. So tan is the angle BC? so it would be 6(26)= 63/27?
no
i have no idea hwere you got 63 or 27 but you misunderstand tan
tan(x) is a function
it evaulates to a number
,w tan(26 degrees)
specifically this number
oh
you want to solve for AB in the equation you have
but honestly you need to watch an introduction to trig video on khan academy or something
looks like you missed it in class
eh.... I get 8 but it's not available as an answer... 
My guess is 4, I’m saying that because it cannot be negative, and 2^x is 1 when x=0 so it’s been moved up by 4 I think? @pastel mauve
what does d(10) represent in the situation? does anyone know how to solve it using my function
HOW DO O SOLVE ALGEBRA
what does the function d mean?
by (a) not yelling, and (b) being a lot more specific about your troubles/doubts/whatever than just "solve algebra"
whats the gradient vector for the function f(x, y) − z = 0
oh for fucks sake.
jeez, why doesn't EVERYONE pile up in this channel. god.
@alpine sable let's move to #geometry-and-trigonometry, otherwise we'll just get shouted over
Ok
what is thisssss
<@&286206848099549185>
<@&286206848099549185>
@acoustic sable
yup
what dose that mean
heres a good introduction
thanks
Where have I gone wrong here or what should I continue with? Am I being completely brain dead and just not seeing what I’ve done wrong ?
nosequepasa
Q.Q
What does it mean to divide?
1 + $\sum_{n=-\infty}^{-1} \frac{t^n}{n} + $\sum_{n=1}^\infty \frac{t^n}{n}$
bunny
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
ye, ty
t = e^i*theta
so, how can i expand this?
this is
1 + ... -log(1-t)
right?
you assumed f(k+1) was true
can anyone help with c 🙏
No I assumed f(k) was true
$2^k+6^k=8N, N\in\mathbb{Z}$
moshill1
I’ve seen that method used on YouTube and I want to use it too, but idk if my spec will allow it
In the textbook it shows only the method I used
Making me think I can’t use that 1
what other method is there...?
try doing f(k+1)-2f(k) and you'll get 4(6)^k which is divisible by 8 for all integers k>0
Or just make a strong hypothesis, namely that f(k)=8N and f(k-1)=8M, N and M are in Z
$2^{k+1}+6^{k+1}=2(2^k)+6(6^k)=2(8N-6^k)+6(8N-2^k)$
moshill1
i need help
hi
hi
ok
im gonna post my question
Write in rational form and then evaluate. Express your answers using only positive exponents. No decimals. Show work.
the answer i got is
yes
ok good is that correct
I said yes...
so is it right?
I already said yes
do you know your exponent rules?
ty
not really
Ok so look at your notes or google them
okay i just did
and what's the answer to your question?
yes
$\int_{\sin{x}}^{\cos{x}}=\int_{\sin{x}}^0+\int_0^{\cos{x}}$
moshill1
each of which can be differentiated with chain rule and FTC
yes I did the splitting, but I still get a different answer
what do you get?
if it’s 13m/s, how much would that be in km/h
how do you get that?
possible for you to post your work?
so I put e^(f(x))^2
nvm i got it
then using chain rule
what's f(x)?
sin(x) and cos(x)
ok so you're doing it in reverse
because younhave two integrals
you do chain rule then sub in
🤨
$f(x)=\int_0^x e^{t^2}\dd{t}$ what's $f'(x)$?
moshill1
$2xe^{x^2}$
time
moshill1
that's what FTC says
time
yes
now $\int_0^{\sin{x}}e^{t^2}\dd{t}=f(\sin{x})$
moshill1
thank you
hello
where should I ask a question regarding functions between contable and uncontable sets
can I ask here ?
Sure
let S be the powerset of N. Now me and my friend, we are dealing with a function from S to Z.
now my first thought was like

wait
the power set of N is the set of every subset of N right
oohhh I think the problem is there
wait okay so S is defined as the set of every subset of N, perhaps that's not the power set of N
but like
my thought was like
S is uncountable and Z is countable right
so now
by pigeonhole
A car accelerates from 0 to 100 km / h in 13 seconds.
What is the acceleration a?
there has to exist at least two elements A and B of S such that f(A) = f(B)
right
(I don't really know much about the terminology used here I'm sorry)
is it constant acceleration?
yes
also use an unused channel
yeah bro pls I'm also looking for help
In the pigeonhole principle, one of your objects must be finite
Which is not the case here
really ?
Yes
I thought there was like a version of pigeonhole that worked for infinite sets
but regardless it's intuitive isn't
like
the cardinality of S is bigger than that of Z right
Yes
the number of "pigeons" can be infinite yes, but then the number of "holes" should be finite
ohhh
okay I see
but even if the number of holes is infinite, if the number of pigeons is bigger than the number of holes, you can derive what I derive right ?
like
arrive to
but then my friend showed me this function
$$f(A)=\prod_{x\in A}p_x$$
Astrolopithecus43
where p_1p_2...p_n are the first n prime numbers
which is a bijection between the powerset of N and the squarefree numbers ?
and thus it's an injection between S and Z?
what
I can't find the error on here
rip
what's going on
help ?
me ? or the other guy ?
mb
oh ty guys
no it isn't
what if A has infinite size
your square-free integer would be infinite? That doesn't make sense
but there're infinitely many prime numbers right
Suppose you take set A to be the set of all even numbers
then f(A) = ?
certainly not an element of the naturals, let alone the squarefree integers
but there's a bijection between the prime numbers and N right
Yes, and?
so for any subset of integers on S, there will be enough primes to construct this product right?
it will be arbitrarily large ?
but mmm
There will be an infinite amount of subsets of N for which f is not well defined
And does not map into the square-free integers
Any infinite subset of the natural numbers like I said
Suppose you take set A to be the set of all even numbers
then f(A) = ?
but there are infinitely many primes tho?
infinity ?
wait
You can't convince me that's a bijection
mmmm
yeah precisely
okay so mmm
what happens if
let's say f maps from S to N
then f({set of natural numbers}) is not well defined either ?
like
cuz for every A in S, we have that f(A) + f(A^c) = f(N)
but then you would need an infinite amount of pairs of integers x + y such that x + y is equal to f(N) right
also so the first reasoning is correct then ?
f({1}) = ?
how can you know ?
lol mmmm
no like
it's just a condition that defines a set of function
like the set of functions that satisfy the equation
mmmmmmmm
okay but the first thing that we said
Ok, so that implies that set contains some functions that you can build explicitly
Can you name one for me?
can someone help me with this, thank u so much
ok so what is it about this f that is so special?
That it's not a surjection?
What are you even trying to do now
okay so look
wait can I dm you the original question?
cuz like we are going to use it on an olympiad
in a month or smth
yes but
the original problem is related to all this questions
and it has to be kept secret
lol
is it okay ?
if I dm it to you?
How is it a secret then
No hablo castellano muy bien, amigo
Hi good night guys
I have a question
idk I thank you a lot for your help bro
good luck anyway
ty
like the main problem was that my friend sent me that construction for an inyection and we couldn't figure out what was up
but ty
tytytyty
is this an exam question?
1/3 = 0.333...
1/3×3=1
0.333...×3=0.9999..
Why is that so why is 1/3×3 = 1 and not 0.99999999999
Just for my own interest in not an math person really but I want to know
I'm
A common question, why does 1=0.999...
If you want to know more, Wikipedia has a good article on the subject http://en.wikipedia.org/wiki/0.999...
I take back the very last thing I said about it being an 'infinitesimal' - that's a 17th century idea that Newton and Leibniz were very keen on, but it was never mathematically rigorous. 200 years l...
no,its for my Homework I just learned the concept yesterday
ok
Thx Ill have a look
it looks like a triangular prism to me
Thank you👍
hello
can someone check if i did this right
Determine the equation of the following exponential functions, in the form f(x) = ab x + c.
<@&286206848099549185>
is that correct
get them both with base 3
I get it ok but I don't understand fully. 0.999 / 2 is not 0.5
yes and i got 1
It is 0.49999995 somethink
,w solve 2x=-2(x-10)
x=1 isnt correct @tacit mortar
oh
$\frac{1}{9}=3^{-2} \ 3^{2x}=3^{-2(x-10)}$
moshill1
so what i did was wrong or was the last part wrong
ok so i had to do more?
ty
Determine the equation of the following exponential functions, in the form f(x) = ab x + c.
For this question the slope intercept would be (0, -1) (1, 2)
and the answer would be y= 3x-1
y=3x-1 isn't an exponential function
Could you answer my question
No
oh so thats wrong
Ugh
14 feet as in diameter?
If x, y, z are positive numbers below 10 and
(100x + 10y + z)^2 = (x + y + z)^5
Extract the value of x^2 + y^2 + z^2
Help?
trigonometric substitution.
whichever you prefer, but try something along the lines of sin(x)^2 + cos(x)^2 = 1
okay let me try
that was funny
Amy makes an initial investment of $5000. The investment loses 13.5% each year.
a) Determine an equation that can be used to model the amount of the investment.
b) How much will the investment be worth after 4 years?
c) How long will it take for the investment to triple?
<@&286206848099549185>
?av
,w 54+36=100
,w 54+36=
,w 64+36=100
I can help
I’m so mad! This keeps happening to me. Sometimes I use PEMDAS on an equation when I can just move all the terms to the left and factor it!
ok..?
do you need help or just ranting in a help channel for some reason
Sorry! I have a question
Give me a sec...
Does anyone know how to solve this? I’m stuck
What happens as x gets large?
When ur free can u help?
y=4^x has a HA at y=0
f has been translated left 1 and down 10
Anyone free to assist me with this please?
@indigo vine @alpine sable in use, read the rules
Oh! Thank you! (Sorry it took me so long. I’m kind of slow) I kind of sort of get how to solve this. I think I need to study asymptotes again.
Is the channel free rn?
Or is someone still waiting
I just started coordinate geometry so I’m a bit stupid. I was told that the point where the bisector meet is the center of the circle and then I just need to find the radius
But something came out wrong on the Desmos graph when I tried to input the values
school laptop so I can’t use discord
Sorry for bad image quality, took it with my phoen
<@&286206848099549185>
the point N is wrong
Wait wot
I am pretty sure point N had the right coordinate
If it is wrong
Would it be possible for u to explain
I am a bit slow to see the problem
so l passes through L(-4,0) and M(0,3)
Yep
so it has a gradient of 3/4
Yes
and a y intercept of 3
Mhm
M is midpoint of LN
Yeh
x and y are independent so (Lx+Nx)/2 = Mx
yh
Struggling with question 13 F
Some thing comes out wrong on the graph when I put the value into a graphing calculator
The points do not line up
And are not all on the circumference of the circle
what's the coord for the centre of your circle?
nvm (1.5,3.5)
i'm seeing something
to do with circle theorem
angle LPN is a right angle and L,P & N all lay on the circumference which matches with the angle in a semicircle is 90 degrees theorem
hence LN is the diameter
which makes M the centre
@uneven isle
i know how to do it via dot product
Just prove that they are penperdicular
I always do it dat way
To prove they are penper just make sure their gradient are the negative reciprocal of each other
Which will always multiply out to -1 as ur result
not sure what year are you but i'm in y12 and dot product is just so much easier
I’m yr 9
that cool man
Imma look into dot product
sure i think you can learn it pretty easily, but understanding it takes knowledge of linear algebra which i don't think a lot of y9s know
<@&286206848099549185>
how do u do this
ive gotten the coordinaates for the vertices & equations for the lines of the triangle but dont know where to go from there
pick a point on the line and then find the area of the rectangle from that point in terms of x or y. Then optimize the function
thanks i figurd it out
@proven mortar That's a derivative, right?
@proven mortar Limits can evaluate to infinity.
I think this is an example where a derivative is infinity:
,w D[1/x, x] at x = 0
No need to ask, just ask your question and people will see if they can help.
@nocturne carbon OK, what's the x value in (1, 3)?
I don’t know 😭
Okay thanks for that
1
7
Good.
Wait if you can, can we do this in dms so I can find the chat again
@nocturne carbon No, sorry, the server rules say it should be done here, but you can copy the chat to Notepad and save it or something.
Okay let’s continue pls
-3 and 6
OK, what's the first minus the second? (-3) - (6)?
3
No, what happens when you start at -3 on the number line and go backwards 6?
Right.
Chai T. Rex
y minus -9 hmmm
Chai T. Rex
Didn’t I just subtract both the y’s
Yes.
Chai T. Rex
OK, let's look at how your worksheet wants you to do it.
Should I send it again
Look at the top. We'll do that and then you can apply it to problem 4.
No, I've got it.
@shell karma Sorry, channel busy.
Yes, that's the slope.
THANKS
Chai T. Rex
IVE BEEN STUCK FOR AN HOUR
For the y I got 5 and for the x I got 8
OK, good. You went the second one minus the first one, which is how they wanted it.
You're welcome.
OK.
I got 3/11
For which one?
5
Yes, that's right.
Okay thank you so much I can’t thank you enough
You're welcome.
Hey guys I’m stuck on this question, anyone know how to start ?
How many subsets of {1,2,3,4,5,6,7,8,9,10,11,12} contain at least 8 elements ?
I know there’s a formula n! / ((n-m)!m!) but the “at least 8 elements” part is throwing me off
Chai T. Rex
Does that part make sense?
Ok so that’s for exactly 8
Hello is this channel free
@tacit mortar No, sorry.
Yes it makes sense
ok ill wait
@brave canopy So, what counts are 8 or more?
Right.
So do I add it all up ??
Yes.
Oooooooh
So do I do the formula 4 times for each one
And then add them together ?
You do the formula once for each one.
Thanks !!!! I was getting confused
ok is this free now
i was here first
POST QUESTIONS GOGO
ok
Determine the equation of the following exponential functions, in the form f(x) = ab x + c.
Chai T. Rex
@vernal crown Sorry, channel busy.
i asked at 8:30
would the slope intercept be (0, -1) (1, 2)
and y= 3x-1
Yes, that's the equation of the line that joins the two marked points.
relate hypothesis testing in a specific situation you experienced or you observed. how important is to follow step by step process? (can anyone help me to answer this question) <@&286206848099549185>
so did i do that correct?
this one
Chai T. Rex
Chai T. Rex
Chai T. Rex
Do you see how I got these?
are those the slope intercepts (0, -1) (1, 2)
Chai T. Rex
oh
Chai T. Rex
yes
OK, how did I get the -1?
from the graph
Chai T. Rex
uhh
,w int x(x+1)^1/2 dx
@sullen nova Please use #bots for that.
Or just use the Wolfram Alpha website directly.
@tacit mortar Stuck?
yes
What is an arithmetic series
Chai T. Rex
@foggy onyx Sorry, channel is busy.
yes
Chai T. Rex
1?
No, in terms of the formula.
Chai T. Rex
Nope
Chai T. Rex
can someone help me with this problem?
@alpine sable Sorry, channel busy.
yes
Chai T. Rex
ohh
Chai T. Rex
so x will be replaced by 0?
Chai T. Rex
yes it is making sense but how did u get 2 and 3
I made them up as an example.
oh
Does that make sense?
f(0) would be f(x)
Chai T. Rex
yes
Chai T. Rex
Chai T. Rex
x can be replaced in the formula for f (x)
f(0) means to replace it with 0
Chai T. Rex
yes
Chai T. Rex
So,
$$f(0) = -1 = ab^0 + c$$
$$f(1) = 2 = ab^1 + c$$
We get the middle part from the graph.
Chai T. Rex
-1, 2 are from the graph?
Yes, that's right.
ok
So, we simplify the right sides. What's a number to the zero power?
number 1
Right.
Hey Chai! Hope you're having a great night/day!
Carry on 😁
What's a number to the first power?
Thanks 🙂
You too.
@pine lake Sorry, channel busy.
Oh ok
any number raised to the power of 1 will be the number
Chai T. Rex
yes
OK, so what happens if we subtract the first equation from the second?
I posted the question
If ur free pls help
Oh, I'm not ready yet, sorry.
it will become 1
Chai T. Rex
See how I subtracted the left side of the first one from the left side of the second one?
And the same with the right side?
oh
@tacit mortar OK, now what y value is it asymptotically approaching as it goes to the right?
on the graph
Yes.
3?
Right.
yes
So, what kind of exponential graph starts going up and then levels off as it starts to go right?
yes
With something greater than 1 as the base, it swoops up like that.
oh
,w plot (1/2)^x
oh
With less than one as a base, it swoops down and then levels off.
yea
yup
So, to get it to approach y = 3 as it goes to the right, we need to add 3.
,plot w -(1/2)^x + 3
,w plot -(1/2)^x + 3
yes
So, c = 3.
yea
Is this channel free now?
@vestal hollow No, sorry.
ok
so it would be
3= a (-4 -1)
Chai T. Rex
Yes.
Chai T. Rex
yes
Chai T. Rex
so -4(b-1)=3?
and i have to solve for b?
ok
@tacit mortar Yes, you're right, but it's not -5.
oops
would it be 5?
Chai T. Rex
finding b and would b 1
is b 5
@tacit mortar No.
Chai T. Rex
-4 -3 = b
No.
What's the last thing you do in calculating the left side?
@alpine sable Sorry, channel is busy.
@alpine sable Please read #❓how-to-get-help.
Is there any addition on the left side?
would u move the -4 over
How?
nvm
You need practice in basic algebra.
You shouldn't be doing these problems if you have trouble in it.
There's Khan Academy online if you want to learn how to solve equations like this.
oh
There's also the "Elementary Algebra" Schaum's Outline if you want a workbook with short explanations and lots of problems and answers.
oh
whats ur grade idkwhat
11
fat cap
Yeah, you need to review solving basic algebra equations quick.
All your classwork will expect you to know how.
So, to get better grades and stuff, please study up.
and where are u getting the questions from
oh
its home work
@tacit mortar Here's a course online: https://www.khanacademy.org/math/algebra. It'll show you how to do stuff like what you were stuck on.
ok thanks
@tacit mortar Here's the workbook if you like that better: https://www.mhprofessional.com/9780071611633-usa-schaums-outline-of-elementary-algebra-3ed-group.
isnt he in high school
i was here first
bro u werent even here
ive been waiting for 1 hour
@pine lake Your addition/subtraction at the end was wrong, I think.
i
@gaunt magnet What was the question?
this i just wanted to make sure i did it correct
.
,calc (-8)^(2/3)
Result:
-2 + 3.4641016151378i
@gaunt magnet What course is this for?
11
Yeah, but algebra, geometry, precalculus, what?
its grade 11 functions
OK, have you learned how to get complex numbers as answers to powers?
yes
OK, 4 is an answer.
,w (-8)^(2/3) real
8x ^4/9y ^5
Looks good, though you should practice putting the denominator in parentheses on here.
ok alr last question
,w 8x^4/9y^5
Yes, looks good.
is is right?
Chai T. Rex
would it be 5 or -5
,w 3^(2x) = (1/9)^(x - 10)
@gaunt magnet 5
ok ty
it's 5 + (ipi)/2log(3)
No problem.
1 + 10 = 11
is true but you haven't finished the problem / found x
would it be 11=11
is true but you haven't finished the problem / found x
ok the final answer would be 1?
no
ideally you'd want to manipulate your equation and isolate x (which will tell you what x is)
i.e. first isolate 4^x
and then apply log/exponent laws (or intuition) to determine the value of x
ok would it be 0?
yes
so i was correct but
i didnt finish
the process is bad
oh
hello
1 + 10 = 11
by itself tells you nothing about what x is
yea
and if you plan to compare 4^x to the 1,
then you're much better off starting with your original equation and subtract 10 from both sides to get:
4^x = 1 directly
which you can then use to deduce x=0
(or apply log_4 to both sides to get the same result)
ok ty
Determine the equation of the following exponential functions, in the form f(x) = ab x + c.
the answer i got for this
was
5
,w solve 2x=-2(x-10)
right?
is it supposed to f'(g(x)) on the right?
i have no idea how what you're doing is relevant the the question
@alpine sable what's written in the image is correct
not different. chain rule is applied there.
hi
Could I please get some help
getting crowded here
but chainrule is f'(g(x)) * g'(x)?
consider that you're taking the derivative of an integral
alr, i'll just remember it's different that way lol
you could go through the long way
let F be the antiderivative of f
=d/dx( F(g(x)) - F(k))
and applying chain rule
= F'(g(x)) * g'(x)
= f(g(x)) * g'(x)
is the base supposed to be a square?
Yes
how did you get 75.6?
I applied the formula but it keeps coming wrong
Let me show you the formula I used
Not sure if it’s the right formula
11= height 3= side length/ base
that's not the correct fomula to apply here
at a glance the h in that formula represents the altitude of the square pyramid
however in this question you're given the slant height
here, you can calculate the areas of your faces directly (simple formulae of areas of triangle and square)
and add them all up
Could you help work it out or provide an example
do you know how to calculate the area of a triangle?
do you know how to count the number of triangles?
do you know how to calculate the area of a square?
do you know how to add stuff?
no weh ma mans
ok?
ayo someone can help me id appreciate it
<@&286206848099549185>
I am done with that I need help with this do
<@&286206848099549185>
multiply both sides times 7 @rigid zenith
<@&268886789983436800> they are getting a bit ping heavy.
@rigid zenith familiarize yourself with the rules in #❓how-to-get-help. in particular wait 15min before pinging helpers, and only ping once
can anyone help
If your question has not been answered for a minimum of 15 minutes, you may use the Helpers tag once. Please do not try to bump your question using this ping unnecessarily. Do not abuse this ping. Do not individually ping users with the Helpers tag without their express permission.
!r4
If your question has not been answered for a minimum of 15 minutes, you may use the Helpers tag once. Please do not try to bump your question using this ping unnecessarily. Do not abuse this ping. Do not individually ping users with the Helpers tag without their express permission.
generally !r# for rule #
Thank you as well.
can i get help with this
Determine the equation of the following exponential functions, in the form f(x) = ab x + c.
the answer i got is -4(1/4-1)=3?
-4(1/4-1)=3
is true but is not an equation for an exponential function
is the 1/4 what makes it wrong?
firstly i don't know where the 1/4 is coming from
and what makes it wrong is that
is not an equation for an exponential function
has no x present
is not in the form
f(x) = ab^x + c
what's the question asking for?
Determine the equation of the following exponential functions, in the form f(x) = ab x + c.
-4 is the a value
1/4 is the b
and your c value?
3
,w graph y = -4*(1/4)^x + 3
when x=1, you should get 2
however according to your values, you'll have 1
your c value is correct, your a and b are wrong
oh 
what do you need help with
Thanks, yeah I realised I was being silly as soon as I clicked post.
how did u find can u explain me
malicious compliance with underspecification
the missing number could be literally anything you want
because you don't give NEARLY enough information
dont think so
you need to be more explicit and use part a
to get that A_ij = (A^T)_ij for i, j in 1:n
Men, I must make an announcement... today this very fine man has passed away... may god bless his soul
hi
I've been breaking my head over an algebraic problem
I'm trying to figure out the phase and amplitude of a sinusoid from two samples. The frequency is know, and y zero is known
An approximation is my case is good enough
This is what i came up with until now
For jotting down and sharing quick calculations. Type free-form text and see the results of any calculations appear in the margin.
at the end there are two equations
with just two unknowns
so i substitute
but then i don't know how to solve for amplitude nor for phase

