#help-0
1 messages · Page 1060 of 1
Just need help understanding what it’s saying lol
What exactly is troubling you
Just the wording
Do you know what the graph of -x^3 looks like?
The wording of the explanation to be exact, I wanted to see if someone can explain it
yes I know what it looks like! It’s the wording part
So as x approaches negative infinity, and where does the graph approach, for the domain?
indeed
It was a question for you to answer
What happens to the domain of the function as x approaches negative infinity?
Closed by @mint hedge
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
I am a bit confused on how I should calculate theta here
especially since there is no reference triangle
sine cosine tan?
no i dont sorry
sorry, forgot to mention r is 1 since we're dealing with unit circles
Which one has x and y?
Then that's fine too
wdym?
Which trig function has x and y
Yes
Closed by @willow elk
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
$(x^2)/7 -(7y^2)/42 =1$
$\frac{x^2}{7}-\frac{7y^2}{42}=1$
I'm assuming I can just divide the 42 by 7 but i need some clarification cause I feel like id need to divide everything by 7
lirmirit
then for $\frac{7y^2}{42}=\frac{7y^2}{7\times 6}$
lirmirit
lirmirit
Closed by @fleet quail
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Find the equation to the circle which passes through the points A (10,-2) and B (27,-19) and has its centre on the line X-15=0. How do I find it?? help would be much appreciated
Is it possible to graph it
I get this because y is 15 but i dont know what to do next
Graph as in graph the points
@quaint otter try and find the midpoint of the y values presented
like this?
-2 and -19?
Check point b
Yes. Find the middle
-10.5?
Yes
Now assemble the equation, and check your solution
We forgot r
got it
For r take the distance between the midpoint and point a or point b
And square it
You might need to find the midpoint of the x values as well
,w midpoint formula
Is the problem saying the center is on x=15?? and A and B are both points on the arc?
How? sorry I dont understand
Oh wait
center is on the x-15=0 line
First, plot the center point
On the graph
Then use the distance formula
I dont know the center
The center is (15, midpoint of y values)
In this case (15, -10.5)
ahh ok
The x value was given, the y value was through midpoint formula
one sec
Something’s not right
How’s the center at x=15
And it’s given heh
Wait a second

AB does not pass through the midpoint
A and B are just points in the circle
This is gonna take some thought
Hi Openglobe, I think you're making a mistake here. Not all lines through a circle pass through the center.
I think I can lend you a hand Sofia
I now realize that
This was a great start
Indeed the y-coordinate of the center will be 15
y coordinate?
So we want to work out what h and r will be, right?
It’s a typo
Whoops! x-coordinate :)
ok ok 🙂
We know that (10, -2) and (27, -19) are on the circle
right
So can you tell me, what does it mean for a point to be on the circle, in terms of the equation you have?
Openglobe, would you mind just letting sofia think for a moment?
both have same distance to the radius?
Imma leave
Just take it from here
Your help was appreciated! thanks
Why does this equation describe a circle? Because the equation holds for some point (x,y) exactly when that point lies on the circle
So what does it mean to say that (10, -2) is on the circle?
theyre both equal to r squared
Sorry this isn't right
hmm
Let me tell you what it means
When we put x = 10 and y = -2 into this equation, we get the same number on the left and right hand side
So what it means for (10, -2) to be on the circle is that the equation is correct for x = 10 and y = -2
Do you agree with that?
sorry where are we putting it?
@lean depot I found the answer. Literally found it by desmos tweaking
You gave us this equation at the start:
I dont know if its dumb question I'm a bit lost
No, it's a good question
That's cool Openglobe, but I'm trying to get Sofia to understand this
I already got the answer I just have to know how to get to it
So I'm just gonna ask, how did you come up with this equation?
15 instead of k
Right OK
because of the graph
So what does this equation mean? Can you tell me what it represents?
So k,h is the centre coordinates
oki
We have a circle with centre (k, h) and radius r
What does this equation mean for the circle? What does it have to do with the circle?
yes thats all i know
Yup I'm right there with you
The thing i know is that when I'm given the centre and the radius i can graph the circle
OK, so that's fine.
So I want to tell you what this equation means specifically
It means this:
A point (x,y) lies on the circle exactly when (x - k)^2 + (y - h)^2 is equal to r^2
So we agree that the question states that k = 15, right?
Now let me ask you
ooh ok
Given that we know that (10, -2) also lies on the circle, what can we say?
right
we could say (10,-15)^2+(-2,-h)^2=r^2?
risky
I wondered if it was just replacing x and y with 10 and -2
Yes indeed you are replacing x and y with 10 and -2
So you did indeed mean (10 - 15) rather than (10, -15).
ahh yes sorry yes i meant that
Great stuff!
So notice something about this:
(10 -15)^2+(-2-h)^2=r^2
This is now an equation with only h and r in it.
This is quite handy!
I want you to simplify this a bit first. Do you think you can do that?
ohh let me guess do i make a system?
Yes that's right!
So okay, we have two unknowns
So we need two equations, right?
How do we get another equation so we can solve for the unknowns?
That's exactly right
gimme a sec please ill write it
Thank you! It would be solving this system for h and r right?
solve for r then replace the r with that?
Mm, I think it might be hard to solve for r without solving for h
mm youre right
Do you remember the two ways to solve systems – elimination and substitution?
Well there's technically a third one.
I think it should be called "equality"
So the thing on top is saying that (something) = r^2
And the thing on the bottom is saying that (something else) = r^2
Now this definitely means that (something) = (something else), right?
true
I think if you observe this, and do some expansion and simplification, you will be able to solve this!
OK, good luck!
Ok I got both values!
@lean depot very nice!! Thank you so much I was so lost you actually helped me understand very patient too
@quaint otter Has your question been resolved?
Closed by @quaint otter
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Closed due to the original message being deleted
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
.close
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
hello! I'm struggling to find resources to explain how the 2n and 1 in the summation is being pulled out by multiplying by n/5. is there a specific formula I should be looking at to understand that portion? thanks!
i'm more confused how the 2n and 1 in the parenthesis gets pulled out to become 2n^2/5 + n/5
its not pulled out
is that just a specific property when i = 0?
i havent checked but my guess is they split into imaginary and real sums
then used a formula on sum(2n+1)
is the 10i imaginary while the 2n and 1 are real sums?
jan Niku
you can see 10 sum(i) still in the second line
so id check what 2sum(n) + sum(1) is
uh the i isn't imaginary, to be clear.
lmao
its the "dummy variable" for the sum
split it
$\sum _0 ^{\sfrac n 5} (2n+1) = 2n \sum _0 ^{\sfrac n 5} (1) + \sum _0 ^{\sfrac n 5} (1)$
jan Niku
and just to be clear, both of those would be n/5 correct?
Closed by @autumn latch
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!

Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
No
@lusty ice Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
the first two are definitely true
c/d have some amount of subjectivity \ opinion but i would say d is easier for anyone to agree with
so my guess is c, but kind of bad question because it's really more about personal preference and what the code requires 🤷♂️
why would d be more agreeable than c
cuz i tested on code its possible to make an inf for loop on python
but then for d the prof slides say this
well for loop is just a very natural way to traverse a variable
its similar to say sigma notation in math
true
thats y i also believe its c
bro.
how is 2 wrong..
2 gives an error wtf
.close
Closed by @tardy trench
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
How do I convert this to 5^k+1
Write 6 as (5+1), and then distribute the 5^k into that sum.
Do you see you can factor out 5^k
Closed by @carmine harbor
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
someone please tell me how i’m wrong
someone please tell me how i’m wrong
impossible to tell without seeing your work
REALLY
what the heck am i doing
it’s really that simple
@vale wigeon thank you i appreciate this server so much
.close
Closed by @livid sail
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
arccos
how does that work
arccosine is inverse cosine
so 8/12 is cos right
@wheat crystal Has your question been resolved?
.close
Closed by @wheat crystal
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
how did my professor handle the 2dx?
i understand the rule involved with the 5,1 integrals
but the 5,1 integral of 2dx
i'm not sure what to do there or what he did
ohh i would get the net area?
4*2 = 8
yep \ $\int_1^5 2 dx = [2x]_1^5 = 2(5 - 1) = 8$
Arya
aaa
so many rules
so one question
is every integral
even if it doesnt have the points of a,b
its all somehow correlated to the concept of net area/total area?
or is it only when a,b is specified
like it confuses me how integrals basically undoes something from a deriative standpoint
but then it also somehow ties into area?

Integral is basically like giving yourself a ... simpler function for how much area under the curve is covered as a function of 'x'
F(x) = int f(x) dx
Given the limits, you're only interested in evaluating the area under curve within particular bounds
.close
Closed by @tropic oasis
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
@winged slate Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
I had a quick question for SSA triangles
How do you determine if it has 0, 1, or 2 triangles given the side length as angle?
do you have an example?
How would I determine if this has 1 triangle 2 triangles or 0 triangles?
I already found angle b = 240.99
Yep I know how to use the two equations
However there was some way using the altitude I believe
But you could just use law of sines and cosines
Is that easier than the altitude method?
.close
Closed by @vale fjord
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Is this written correctly?
alright, thanks
better the other way around if anything. z=a+bi in C
@dusky igloo Has your question been resolved?
Closed by @dusky igloo
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Can someone help me calculate this derivative
chain rule, no?
could you please show me?
do you know the chain rule
I'd start with viewing 1/V as V^(-1)
and then?
Applying the power and chain rules yields that derivative of 1/V is -V^(-2)*dV/dt
Yeah makes sense. Thank you
@teal garnet Has your question been resolved?
Closed by @teal garnet
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
use desmos
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Hi, is a normal operator under $\mathbb {R}$ also a hermitian operator?
Itamar
@fallow valley Has your question been resolved?
<@&286206848099549185>
I think so, the definition I know is that if $f is an operator, f=f*$
Itamar
$f\circ f*=f*\circ f$
Itamar
Yeah, $If <\cdot,\cdot>$ is an inner product space, f operator, then $<f(u),v>=<u,f*(v)>$ and in matrices under $\mathbb{R}$ we'll get for a matrix A, $A*=A^t$
Itamar
Yeah
Ok so I found a counter example thanks for the help! if you take 2x2 matrix where 1,1,-1,1 are the values. It will be normal but not hermitian. What I meant was that all values were real
.close
Closed by @fallow valley
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
not sure what i did wrong
$\sum_{n=1}^\infty \left(\frac{1 \cdot 3 \cdot 5 \cdots (2n-1)}{2\cdot4\cdot6\cdots(2n)}\right)^3$
metnal
omg
im so dumb
it should be 2(n+1)-1 so 2n+1
😭
3/10 for that fucking stupid mistake....
@alpine sable Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
.open
What's the best way to prepare for my maths test, it's in 5 more days, anyone got any tips for me <3 ?
Aight ty
what does this mean btw
why did they do 1/2
oh wiat
nvm
cause its triangle area x height i get it mbb
@white pike Has your question been resolved?
Closed by @white pike
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Working on a larger problem, I got this as a part of an equation. Wasn't sure how to approach, so plugged numbers in. Got the Bernoulli Triangle sums [(1), 1, 3, 8, 20, 48]. I worked out that the sum permutation on the right -- if isolated -- form the fibonacci numbers.
Closed by @quasi rover
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
illegal maths?
by multiplying the top and bottom by sqrt(2)
im dumb
@tidal zealot Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Heyhey, i have a question about how a vector formula comes to be
How does the first formula (proj(a onto b) =...) become the second one?
@silent crane Has your question been resolved?
@silent crane Has your question been resolved?
Closed by @silent crane
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
how do i solve the last question?
Closed by @lost coral
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
I'm supposed to find the exact value of sin cos and tan of the angle and I'm not sure how to do it
(-4, -5) are x, y coordinates. What's the horizontal distance?
wdym by horizontal distance
The distance along the x axis
its unknown
What is the distance along the x axis you had to travel to get to that point?
oh -4
-5
So you know the sides of that triangle
so how do i find the sin cos and tan of the angle i just find the angle of the triangle and add 180 to it?
sin = o/h cos=a/h tan=o/a
So if the angle theta is here, how would you make the ratios for each?
Then make it into quad 3
tan=-5/-4
-5 squared + -4squared = hyp
a squared +b squared = hyp
Yes
so then hyp = 6.32
so do i just add the angle of the triangle to 180 to find the sin cos and tan
Yes
Closed by @eager jackal
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
Hiii
Two things you can do
First I got the derivative with respect to x
Find the absolute minimum and max
I got the value of sin
If you're learning calculus, then I would find absolute min and max and use IVT
So sinx=-2
buddy
You can use function behavior to skip using derivatives
Wdym
2x will have more of an influence on growth than cosine
Therefore, just take the limit as x approaches to negative infinity and the limit as x approaches positive infinity
Since 2x has more of an influence, you can visualize what the graph would look like
Thank you for giving me more than 1 method
But I want to know what's wrong with my method
Bc to me it seems correct
Why
What does that do
And you can use periodicity
Bc I differentiated both sides with respect to x
What does it do setting it equal to 0?
It just takes longer work
How does that help you prove anything?
You can show its monotone
You can find extrema since they occur periodically and then use IVT
I have no idea why you are solving for 0
But I would just use function behavior
(Seeing it also has no solution)
I want to prove that it has one real root so if I solve the equation and get the roots ill prove it
How is setting derivative equal to 0
The derivative doesn't equal to 0 ever
Not a terrible idea to set the derivative to 0
Showing how many roots it has?
That only works if the derivative can equal to 0
It gets you an idea of the function
Bro I have a question
And it doesn’t help at all still
It could be equal to 0 inf amount of times
And still only have 1 root
Now if I differenttiate both sides with respect to x now d/dx(0) = 0
So what is wrong
So again, I ask, what does this do?
Are you even reading anything I am saying?
What you are doing doesn’t prove anything
@tepid drum the problem with taht is that the derivative can never equal to 0, so it is hard to find any extrema that way.
The question wants me to prove that the equation has only 1 real root
They want to use IVT
And setting derivative equal to 0 does nothing
I get the roots and check if it has 1 real root then provedd
Setting the derivative to 0 certainly helps
By finding a minimum and maximum and using IVT
You didn't lemme continue
But the problem is that the derivative will never equal to 0
Derivative could be equal to 0 inf times
I now get cos after I have the bus of sin man
.
Still doesn’t prove anything
Bro wait lemme tell you what I reached
Right but it's not a bad idea
Can you check what I reached and tell me where I am wronggg
And can give you insight for what to do
The derivative cannot equal to 0
That's where you went wrong
Normally you can
You could have derivative have inf times be 0
Bro the equation is 2x+cosx= 0 so after differentiation both sides with respect to x I'll get 2-sinx= 0 now sinx= -2 And then cosx = +-rad(-3) and since all roots are complex then there is no real roots and this is wrong bc the question says that there is 1 real root now where is my mistake
Wow this channel is toxic as hell
Doesn’t show anything
If you use that between an interval of a continuous function and find the minimum and maximum, you can state that there are roots if you use IVT, but only if the derivative can equal to 0
In this case, you cannot
So you have to use function behavior
It showed that there are no real roots
No it doesn’t
But my answer has a mistake
@tepid drum setting the derivative = 0 only shows the existence of a maximum and minimum, if any
Not roots
I used the derivative =0 to get the value of cosx
Thus there are no real solutions to the equation bc in 2x-cosx cosx isnt realll
Does x=0 also have no solution?
Because taking derivative we get 1=0
Which has no solution
Do you maybe accept now you are wrong and will listen?
The value of cosx... where? Not at the root
Ik that I have a mistake
The mistake is that the derivative can never equal to 0, so you can't use that method
Ok you told me that getting derivative won't prove any thing
Setting it equal to 0 wont*
What if it could? Setting the derivative to 0 gives the max/min, but I don't know how that relates to the roots
I used this derivative =0 to get the value of cosx which would prove things
Then yeah, you can use IVT on an interval to prove that roots exists
Value of cosx where? At the extrema. There are no extrema though
Now if sinx = -2 use the identity cos^2x +sin^2x = 1 and get the value of cosx
Thats what I did
Can we stop talking about taking derivative and solving for 0
Value of cosx where? cosx doesn't just have a value, it's a function
After i did this I got no real values of cosx
It's wrong but show me where am I wrong I want the reason where I am wrong
Everything you did was wrong basically
A simpler example which clearly shows it makes 0 sense
You've proven there is no relative max/min. That has nothing to do with the roots, though
No max/min on the reals, anyway
So you gotta use function behavior
I got cosx = +-rad(-3)
Did you read this?
And that's not a real number, so there is no relative extrema. Again, that's not related to the roots
Simple yes/no @tepid drum
Ok now cosx= complex number so 2x+cosx is complex
It can't be real since cosx is not real
Doesn't that make sense
Come back when you want help
It's complex at the extrema, but we don't care about the extrema
Because doesn’t sound like you want that
Yes i read what you said above
So agree derivative not being equal to 0 doesn’t mean original function doesn’t have a root?
I want to understand I don't just want to know the right answer
Simple yes/no
Btw I didn't say that
Simple yes/no
Yes
Okay so lets stop trying to set derivative equal to 0?
Why
Since that doesn’t show anything about roots
?
Like we just agreed?
Ok now I want to ask you a question
“Yes I understand why setting derivative equal to 0 doesn’t show anything from above example”
“Wait why don’t we do it now”?
You can’t have it both ways
If you have a number x + rad(-3) = 0 does that sound like x has a real root
Cosx is only √-3 at the extrema, which is irrelevant to the roots
So really sounds like you meant no here instead of yes, otherwise no idea why you ask “Why”
What you said was an idea in general but that doesn't mean that it is the case for every function
A counterexample shows we can’t do it
Because I just showed it doesn’t prove anything
Sometimes the derivative may be different than 0 and the function has no roots ??
But I proved it does after getting the value of cosx
No it doesn’t
Sometimes a function has a hole somewhere while also having an asymptote. Doesn't mean the two properties are related
Ok that's a reason
It gives extrema not roots
Now I understand where my mistake was
So can we agree soon that setting derivative equal to 0 doesn’t do anything?
Yes agreed
Yes bc it would just show values at extrema
Now I got the idea
So I should think in another way
(Also said that a couple of times that extrema is not root) but anyway moving on
Try showing its monotone
What is a monotone
Only increasing/decreasing
I heard that word before but I forgot what it means
Ohh
So I see if the slope is >0 or <0
Right ??
Check if derivative is >0 or <0 for all x
Increasing
Okay so if we can just find a value of x such that f(x) is less than 0
And greater than 0 of f(x)
It must also hit 0 (why)?
Bc when f(x)<0 Then it is below x-axis and if it is >0 then It is above it so to go from this value to that it should pass through x=0
Which is the x-axis
And also f(x) is defined when x=0
Have a theorem that says that?
Intermediate value theorem ?
Yes
Ok that would prove that there is at least 1 real root
But the question wants me to prove that there is exactly one real root
?
You've already proven it's monotonic, right?
Bruh
Bro I am stupid
Idk man but I am In stupid mode rn
Anyways tysm all of you and sorry if I annoyed you
.close
Closed by @tepid drum
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
33 total
how many students that participates in band also participates in track
so 9/33
That’s it
I’ve been looking at this formula
Holy
I didn’t need to do all that
What’s wrong with me
.close
Closed by @clever summit
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
-10(cos4x)^2=-5cos8x-5, how can i generalise these equations
you can divide both sides by -5 first
and then use the rule
$$cos(2x) = cos^2(x) - sin^2(x)$$ i guess
MarveI
wait nvm, idk what generalisation means
wait actually nevermind how do you just generalise the lhs of that: y=-10(cos4x)^2
Generalisation: what the transformations do to the function, and would the same apply to all functions of that type.
so you want to describe what transformation had been done to go from y=cos^2(x) to y=-10cos^2(4x)?
basically do this y=-10(cos4x)^2 and make it a(cosbx)^e
and describe what changing each letter does
right
hence transformations
basically you want to describe how each parameters a, b and e changes the function
well i suppose you can start taking one of the parameters as a constant first and then describe whether the graph is being rotated, stretched out or compressed, or translated compared to the graph of cos^2(x)
this should not be hard since you should be familiar with these transformation
for the exponent (parameter e) tho, you might need to do some calculus
i think for e
it doesnt matter because my graph has to be sinusoidal so changing e makes it not sinusoidal unless it become ^1 which still works
any other changes makes it not work
so for e the only change that could occur would be e=1
actually no, i misremember
(cosx)^a is sinusoidal for even natural a
or well if you like to define sinusoidal as periodic
yep periodic too
so basically the thing is, for cos^2(x) and other similar functions, there is a double angle identity which can be used to rewrite the functions in terms of cos(2x)
but for any even power higher than that, it turns into an addition of sine and cosine
so technically, your function is still periodic
but it does not look like a sine wave
right, so that should restrict your power to being less than or equal to 2
so e<=2 has to be made
and that your power has to also be a natural number that is
and the for the other parameters, they are just like how the coefficients a, b and c in af(bx)+c transform the function
which i hope you know
i guess you will want to compare this transformation to cos(x)
yes a for amplitude, b for frequency, tehcnically c inside bracket for phase shift but there is none in this case and d for mean line
hm?
the easiest one to remember is the constant c, c translates the function up and down by c units
coefficient a represents a vertical scaling, basically compresses or stretches the function in the x-direction
and b represents the horizontal scaling
there is technically also the transformation of translating the function in the horizontal direction, but that is not need to describe the transformation here
this is what best represent your "generalisation"
so for example if you compare your function acos^2(bx) to cos(x), you will need to do some algebra first to rewrite cosine squared in terms of cosine first, then describe the transformation as mentioned above
you could also, compare the transformation to sin(x)
it would just differ by a phase change
so do i describe what the transformations in my equation does like y=-10(cos4x)^2 eg the -10 does this, 4 does that, ^2 does this and then after that use this acos^2(bx+c)+d and from this i change the a value for example and state what that does, then b,c ,d
yes
but again, you need to compare the transformation against another function of similar property
it would only makes sense then
my function is this y=-10(cos4x)^2?
for example, i would want to describe the transformation done to 2x^2-4x+7 compared to x^2
but not x^3
because x^3 is nowhere near similar to a quadratic function
sure
is the base equation just y=cosx^2 then
and then i add acos^2(bx+c)+d these transformations and describe what it does to the base of y=cosx^2
sure
or it could even be cos(2x)
or cos(x)
or sin(x)
or even some as absurd as cos(pix)
honestly, i dont know, it best describe by using derivatives
since changing the power of a function changes a lot of properties which the function has
thats why i thought to keep it standard cos^2x since i dont know how to describe any changes above ^2
for cos^n(x), there maybe a nice pattern to it, or not
ill probably keep base equation cos^2x then
sure
but say changing ^e has to be <=2 otherwise it becomes not sinusoidal and also has to be natural numbers
thats all for the power transformation
since i cant describe the properties it changes
does that work
@rigid smelt
sure
i'll try and see if i come across any problems
do you mind if i contact you if that happens
okay thanks for ur help
@keen portal Has your question been resolved?
@keen portal Has your question been resolved?
"coefficient a represents a vertical scaling, basically compresses or stretches the function in the x-direction" can i describe this as the graph dilates vertically by a scale factor of 10 or would that be incorrect.
@keen portal Has your question been resolved?
.close
Closed by @keen portal
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
could I not calculate the limit like this ?
Closed by @keen python
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
how can this limit be 0 ?
Why do you think it’s 0?
geogebra says so
are you sure?
chances are you are probably using it incorrectly
ah...
i had to show more numbers
in the settingsi only had 2 decimals
i was worried for real xD
thx !
im used to geogebra from school
how can I show this ?
ive tried this but i dont know
I thought I could use squezee theorem (sandwich)
You might have more luck using l'Hôpital's rule
Exactly
but is my approach wrong ?
I don't think so, it seems correct
Just one to remember: using l'Hôpital you can show that $\lim_{n \to \infty} \frac{x^n}{e^x} = \lim_{n \to \infty} \frac{\ln(x)}{x^n} = 0$ for all $n \in \mathbb{N}$
Yuese
I see thx
if its > 1 then its divergent right ?
but im not sure if Ive done it correct
2/3 is not greater than 1
@keen python Has your question been resolved?
,calc 2/3
Result:
0.66666666666667
Closed by @keen python
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
volume = pi integral (limits a,b ) y^2 dx
y^2=(f(x))^2 ???
partial fractions
u get -8/(x+1) -4/(x+1)^2+9/x
integrating that u get -8ln(x+1)+4/(x+1) + 9lnx
and then sub limits
@dusky blaze Has your question been resolved?
.close
Closed by @dusky blaze
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
okay so
why is square root of negative numbers with an i? How is that possible? Why not undefined like ÷0
i is used to represent these numbers because they’re called imaginary
It is undefined in the world of real numbers, but mathematicians long ago made a new type of math (world of numbers) called complex numbers to allow for i to exist
A general solution to the cubic equation was long considered impossible, until we gave up the requirement that math reflect reality. This video is sponsored by Brilliant. The first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription.
Thanks to Dr Amir Alexander, Dr Alexander Kontorovich, Dr Chris Ferrie,...
This is an incredible video by Veritasium
It will likely interest you
oh and one more thing
Are Sin A and Sin B same thing?
Only if A = B + (some integer multiple of 2pi)
(And A and B are real numbers)
.close
Closed by @cyan merlin
Use .reopen if this was a mistake.
Please take a minute to participate in [our survey](#changelog message) if you haven't already!
Thanks
Np
Send your question here to claim the channel.
Remember:
• Ask your math question in a clear, concise manner.
• Show your work, and if possible, explain where you are stuck.
• After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!
Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.
i factored out the first fraction to see if that would make things easier but i don't know where to go from here
Post that work
So notice how the equivalent expression is just the factors
yes
You want to factor the second fraction so it cancels stuff out, correct?
i think so, yes
What in this fraction should be canceled out so you can get the equivalent expression?
x+5 from top and bottom
What else should be canceled out?
I'm not sure... that's all i see
In general, what is needed to be canceled out from that fraction?
Not things that you can see that can be simplified
So I'm saying that the equivalent expression is (x + 2)/(x - 6). This is the first fraction, things need to get canceled out in both fractions to result the equivalent expression. The noticeable one that cancels is x + 5 since it's in that same fraction
So should the x + 2 get canceled?
no, i believe not. i think that because it is in both expressions
but im not sure
So this is what I'm asking. Say you have something like this, and you want a/d as the equivalent expression. You can easily see that the b's cancel
yup
