tu n'as pas un chapitre sur les intégrales ?
#help-13
shut otter
Ah si je lai vu plus tôt dans l’année
mental trail
faut chercher là dedans alors
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sly echo
The diagram shows the cuboid ABCDEFGH
AF = 11cm
CF = 7cm
AĈF = 36º
Find the size of angle CÂF
Give your answer to 2 decimal places.
I'm struggling to change the cosine rule
c=(a2+b2﹣2abcosγ)^-1 to a = something
sly echo
.close
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verbal nymph
Could use some help solving.
cedar kilnBOT
Could use some help solving.
digital cliff
you know what dV/dt is if thats a clue
warped zephyr
I would try and find the volume and with the volume you can compute the radius
sullen heron
What is the difference between an absolute max and an local min on for a trig function?
sullen heron
and does the function
y=5cos(2pi/5 x)+2
have a absolute max on the y-axis or a local max?
proud vigil
What is the difference between an absolute max and an local min on for a trig fu...
there is no absolute maximum for trig functions, unless the domain is restricted
at least, an absolute maximum point
the actual maximum (its treated more like a supremum here, if you know what that is) is whatever the amplitude of the function is
proud vigil
and does the function
y=5cos(2pi/5 x)+2
have a absolute max on the y-axis or ...
read what i said
sullen heron
read what i said
So that would mean the max which is the amplitude for trig functions is more like a local max then a absolute?
proud vigil
So that would mean the max which is the amplitude for trig functions is more lik...
yes
like, if you're talking about a point, yes
because then several points would satisfy the absolute max, and an absolute max is one that only exists for a singular point
sullen heron
yes
Okay so if I may ask
How would I change my function to create a absolute max on the y-axis?
proud vigil
Okay so if I may ask
How would I change my function to create a absolute max on...
restrict the domain s.t. it has an abs. max
sullen heron
y=5cos(2pi/5 x)+2
So for this function what would I restrict?
sullen heron
restrict the domain s.t. it has an abs. max
Can you show me how that is done please
proud vigil
y=5cos(2pi/5 x)+2
So for this function what would I restrict?
graph it first
make sure that it is one-to-one
then you can determine a max
sullen heron
graph it first
Okay so I graphed it and I have my max at 7 since its raised 2 up from 5, and my period is at 5
So now what would it do next?
proud vigil
Okay so I graphed it and I have my max at 7 since its raised 2 up from 5, and my...
restrict the domain to 4<x<6
or whatever makes (5,7) or (0,7) the abs. max
sullen heron
like how do I show that on desmos?
proud vigil
like how do I show that on desmos?
put besides the function {4<x<6}
sullen heron
Like this?
sullen heron
put besides the function {4<x<6}
is this what its supposed to look like?
cedar kilnBOT
@sullen heron Has your question been resolved?
sullen heron
<@&286206848099549185>
I still don't understand how to create a cosine function with a absolute max on the y-axis while also having a period of 5
proud vigil
<@&286206848099549185>
I still don't understand how to create a cosine function...
if a function has a period it doens't have an absolute max since it isnt bijective
or at least bijective in a local neighborhood
sullen heron
if a function has a period it doens't have an absolute max since it isnt bijecti...
Oh, Is it alright if I send the question here since I still dont understand if I completed it correctlyt or not
proud vigil
Oh, Is it alright if I send the question here since I still dont understand if I...
yea
sullen heron
yea
Graph a function with the absolute max occurring on the y- axis, the period of 5 and one other transformation of your choice.
The other transformation\ was 2 vertical shift up
proud vigil
or at least bijective in a local neighborhood
the reason why i say this is because things such as cubic functions (which arent always bijective) do have absolute minima/maxima
proud vigil
Graph a function with the absolute max occurring on the y- axis, the period of ...
hmm
one sec
ill try to graph it on desmos
sullen heron
Okay thank you
proud vigil
it has a period 🤦
good thing i had a doubt
but you still have to restrict the domain to an extent
@sullen heron
sullen heron
Oh so does this function satisfy the question?
sullen heron
but you still have to restrict the domain to an extent
The thing is though does this show the period accurately?
Since the period is 5 the graph doesn't show the period at 5 since then it would turn the absolute max point into a local.
proud vigil
The thing is though does this show the period accurately?
Since the period is 5...
it does
the interval given is >5
sullen heron
the interval given is >5
ohhh so it fine
sullen heron
the interval given is >5
okay wait so since i raised mine 2 up should it change the restrictions like this
proud vigil
okay wait so since i raised mine 2 up should it change the restrictions like thi...
yeap
u got it
gg easy noobs
sullen heron
yeap
oh okay just as a question if could this also be done with a tan or cot function or not since they have different periods and restrictions?
proud vigil
oh okay just as a question if could this also be done with a tan or cot function...
different periods. so slight modifications
sullen heron
different periods. so slight modifications
oh okay and this was the only function that asked for a absolute max but for functions with local max's and min's they would just look like this right?
with the max or min on the point 0
proud vigil
oh okay and this was the only function that asked for a absolute max but for fun...
yeap
sullen heron
yeap
and just one last questions (thanks for all the help)
Graph a function with an asymptote on 7 that goes to negative infinity as it approaches 7 from the left and positive infinity as it approaches your 7 from the right.
is this correct?
the function is y=-\tan\left(\frac{\pi}{2}\left(x-8\right)\right)
eager wraith
sullen heron
.close
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proud vigil
and just one last questions (thanks for all the help)
Graph a function with an ...
yeah thats correct
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lunar sequoia
Hi I’m dumb what’s $$e^{2\ln{1.2}}$$
cedar kilnBOT
Hi I’m dumb what’s $$e^{2\ln{1.2}}$$
wraith daggerBOT
Faduzzle
frigid dust
remember that $e^{a\ln(x)}=x^a$
wraith daggerBOT
Bonk
lunar sequoia
Ah
digital cliff
youre so speedy today
lunar sequoia
Okay perfect ty
frigid dust
youre so speedy today<:catgiggle:912459497954500659>
speedrunning
do you know how to go from here?
lunar sequoia
Yeee
Tyty
Quarter just started and I forgot my basic algebra
In my partial diff class
frigid dust
i know the feeling
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@lunar sequoia Has your question been resolved?
plush ocean
Hallo can someone give me some hints?
cedar kilnBOT
Hallo can someone give me some hints?
plush ocean
I'm having trouble proving the forward implication i.e (p is odd) -> (p = 2l +1)
with only the things i'm allowed to assume
If i were to do this without limits, I would do something like being p is odd means it is not divisble by 2, which leads somewhere to p = 2k + r
which i would want to use the division algorithm to restrict the values of r to 0 or 1
but the thing is i cant assume that here
this this is the first week of proofs (students are only assumed to have calc 2 completed), i dont think my prof wants me to prove the well ordering principle -> division algorithm
dull oxide
but the thing is i cant assume that here
Maybe a proof by contradiction
Hm that might just be the same problem
plush ocean
Maybe a proof by contradiction
I'll probably ask him asap -- or maybe he will just let us assume all integers can be expressed as 2k or 2k+1
dusk goblet
contradiction would be the best approach here and it follows immediately
dull oxide
Okay. Lets say $p$ is odd. Then it is not even. So for every $k\in\bZ$, $p\ne 2k$. The question now becomes, what does it mean for two integers to not be equal?
wraith daggerBOT
SWR
coral jewel
I'm having trouble proving the forward implication i.e (p is odd) -> (p = 2l +1)
try to use induction
coral jewel
base case: p = 1, odd because p = 0 * 2 + 1
assume true for all p = 2m + 1. prove p + 2 is odd
then just prove p is odd iff -p is odd
plush ocean
oooh interesting
hushed folio
You'll have to consider negatives though
for this we could just do two inductive proofs
plush ocean
ill try all the ways and see how they go
hushed folio
one in the positive direction one in the negative
dull oxide
base case: p = 1, odd because p = 0 * 2 + 1
assume true for all p = 2m + 1. prov...
This base case is incorrect
coral jewel
it's a typo, sorry
dull oxide
Equivalence relations might be a good strat if you are familiar with them
dull oxide
Sounds like you have plenty of ideas though, so i won't overload you
plush ocean
thank you regardless, ill try all of them :D
fierce laurel
cedar kilnBOT
fierce laurel
I thought "if and only if" meant both P --> Q and Q --> P must be true
here, P --> Q is true but Q --> P is false
proud vigil
I thought "if and only if" meant both P --> Q and Q --> P must be true
i don’t se the problem here
the answer is false
becuase the converse is indeed false therefore the statement is
void sand
oh hold on
fierce laurel
I'm talking about #4
"diamond is purple" is P. "the circle is blue" is Q.
This is true. Therefore P --> Q is true.
Also, Q --> P from the problem statement is false. This means that P- OH. It's saying NOT blue.
proven nova
it's saying P <--> -Q
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potent flower
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potent flower
shouldn't we use right handed coordinate systems
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@potent flower Has your question been resolved?
restive oriole
shouldn't we use right handed coordinate systems
I don't think it matters
heavy canyon
Hi, I don't remember anything with trigo and I want to understand how to do this
heavy canyon
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@heavy canyon Has your question been resolved?
heavy canyon
I don't understand the thing in the left
10pi over 7 , 13pi over 7 How do I know if my remarqable point are in that
heavy canyon
.close
idle gulch
n(n+2) = 52+(n+4)
earnest idol
52 should be in the rhs
hollow trail
if it says consecutive even integers, that would imply all of them are even
earnest idol
also the numbers should be 2n, 2(n+1).. ig
idle gulch
I didn't notice, they said "even integers"
earnest idol
it says the product is 52 more than the third
idle gulch
(product of first and second) is 52 more than the (third)
earnest idol
5 is 2 more than 3
idle gulch
5 is 2 more than 3
Lol
earnest idol
its just an example
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gaunt bough
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gaunt bough
When does Eulers Formula not apply?
idle gulch
I think it was valid for closed surfaces only !
cedar kilnBOT
@gaunt bough Has your question been resolved?
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gaunt bough
.reopen
cedar kilnBOT
✅
gaunt bough
how do you decide if it is a closed surface
idle gulch
"A closed surface is a three-dimensional shape that completely encloses a volume without any openings, edges, or boundaries."
Also it must be a convex polyhedron !
cedar kilnBOT
@gaunt bough Has your question been resolved?
gaunt bough
in terms of these diagrams, how do you determine that
because they are 2d and composed of just lines
do you mean that every vertex is connected to all other vertices?
cedar kilnBOT
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icy siren
Hi, Im just feeling a tiny bit unsure if I did this properly if someone can check. I had more trouble with 6c specifically as well. Thanks!
cedar kilnBOT
Hi, Im just feeling a tiny bit unsure if I did this properly if someone can chec...
@icy siren Has your question been resolved?
icy siren
<@&286206848099549185>
ionic finch
$P{ |X - \mu| < 2\sigma }$
wraith daggerBOT
Dubs
ionic finch
This is for part c)
which is exactly what you have did
$P{ |X - \mu| < 2\sigma } = P{\mu -2\sigma< X < \mu -2\sigma}$
wraith daggerBOT
Dubs
ionic finch
@icy siren
I’m seeing a possible error in the last step, why did you subtracted P{X <=7}
icy siren
I’m seeing a possible error in the last step, why did you subtracted P{X <=7}
Yes
to find the inbetween since
it asks to find the within
if we subtract 8 then it wont be within 8 and 15, it will be 9 to 15
cedar kilnBOT
frigid dust
<@&268886789983436800> troll
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proper fox
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celest seal
proper fox
Sorry.
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Available help channel!
magic ore
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carmine bronze
What have you tried?
magic ore
using lhopitals rule and i got (1/x)/2x
slate lintel
seems like a good start
magic ore
do i need to take the second derivative
slate lintel
simplify it a bit
magic ore
??? what part should i simplify
wraith daggerBOT
hayley, who shakes the world
slate lintel
which is the same as $\f1x\cdot\f1{2x}$
wraith daggerBOT
hayley, who shakes the world
cedar kilnBOT
@magic ore Has your question been resolved?
magic ore
the answer is 0.5?
slate lintel
show your work
wraith daggerBOT
hayley, who shakes the world
signal verge
Can anyone help
cedar kilnBOT
Can anyone help
frigid dust
!da2a
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@signal verge Has your question been resolved?
vapid radish
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vapid radish
Why is the bottom angle 170 deg from the ground?
vapid radish
idk how to explain it but a plane flies so it goes 50 in the x axis and 250 in the y axis
yeah
wait i think i figured it out 😭 its because its a upside down right angle
clear ember
this angle is 170
how
vapid radish
so its 180-a
frigid dust
how
because a is roughly 10
and thats from the vertical
so the other angle is 170 from the horizontal
clear ember
the triangle containing the red wouldn't be an euclidean triangle though
if red was 170
a + 90 + red > 180
clear ember
v1 and v2 are perpendicular
using this
vapid radish
its because I calculated this one and the question was whats the angle against the ground aka
clear ember
can u just post the original question
frigid dust
!original
cedar kilnBOT
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
vapid radish
I mean I already figured it out
its forces which create a right angle triangle
i think
clear ember
i have a strong feeling that u actually haven't figured it out
as in you have a wrong reasoning in your head
if i were to guess what the actual question is
it's asking for the bearing of your resultant velocity
this is how they got 180 - a
because bearing uses north as reference and then calculates the angle clockwise to your resultant
vapid radish
I mean its just 2 right angle triangles perpendicular against eachother,no?
clear ember
what
i can kinda tell you it has nothing to do with this
but sure go ahead and redraw it
vapid radish
frigid dust
that should be 90
muted timber
A-90, not -180
frigid dust
A-90
vast ermine
Help please
cedar kilnBOT
Help please
frigid dust
!status
cedar kilnBOT
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
I used this formula following a walk through
But I don't understand it
Or how it works
I know circumference is the whole but why do you multiply that by (angle divided by 360)
vast ermine
And why do you divide the angle by 360 (I know angles in a circle add up to it)
frigid dust
you want the part of the circle
vast ermine
And I don't wanna memorise it without understanding
frigid dust
you know the whole circumference is 2pi r
vast ermine
Yes
frigid dust
and we only have a segment of it
in particular, that segment is 50/360th of a whole circle
vast ermine
ohh so you find 50/360 of the circumference
vast ermine
Ohh so instead of doing circumference x 50 and then divide by 360 we just multiply by 50/360
naive talon
Ohh so instead of doing circumference x 50 and then divide by 360 we just multip...
Yep.
cedar kilnBOT
twilit escarp
,rotate
wraith daggerBOT
twilit escarp
Limit from right is not equal to limit from left
safe yew
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gentle stirrup
https://math.stackexchange.com/questions/324527/do-these-equations-create-a-helix-wrapped-into-a-torus Is it possible to rewrite this equation in isometric form? I wouldnt know where to start doing this. I think for someone this might be fun. Ideally the equation would make the shape like the one 6, 1, 10 paramaters set. to be honest i want this to be used with world edit in minecraft for a project my university is working on (long story). is it even possible?
cedar kilnBOT
https://math.stackexchange.com/questions/324527/do-these-equations-create-a-heli...
@gentle stirrup Has your question been resolved?
gentle stirrup
<@&286206848099549185>
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@gentle stirrup Has your question been resolved?
west kiln
can someone explain me the pliers criterion?
cedar kilnBOT
can someone explain me the pliers criterion?
west kiln
this is how it is in english , on Romanian we say "criteriul clestelui"
cedar kilnBOT
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west kiln
.close
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azure glade
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azure glade
not sure what to do here
i think the question is asking to show f'' has at least two zeros in [-1,1], but f'' = 0 doesnt necessarily confirm you have an inflection point
so im confused
twilit escarp
It must change sign indeed
So i don't think the question want you to show that there is two 0 for f" but also that it changes sign between those zeros
azure glade
So i don't think the question want you to show that there is two 0 for f" but al...
but doesnt a change in sign imply there is a zero
twilit escarp
Only if continious but yes i believe this is right
azure glade
and since f is continuous on [-1,1] if it wants me to show changes of sign it wants me to show zeros
twilit escarp
Yeah but once the zero found you must find the sign
Which is why i advice to do an inequality instead of an equality
f" >= 0
Then you have where pos and the 0
And anywhere else is negative
azure glade
ohhh
f'' > 0 would show regions of concavity right
and if theres regions of concavity then there must be points of inflection
twilit escarp
Its better to do >= cuz the equality case gives the 0 of f"
twilit escarp
f'' > 0 would show regions of concavity right
Concave up yeah
twilit escarp
and if theres regions of concavity then there must be points of inflection
Since it is continious yeah
ornate cypress
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kindred storm
,rccw
wraith daggerBOT
frigid dust
!status
cedar kilnBOT
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
@ornate cypress
ornate cypress
Ye?
kindred storm
What step of the above are you on?
kindred storm
Which theorem?
ornate cypress
The 5th theorm
kindred storm
,rccw
wraith daggerBOT
ornate cypress
Here the limit x tends to 0,but if we multiply and divide a and b respectively, ax and bx do not tend to 0
kindred storm
a would be a constant, so if x goes to 0, a constant multiplied by x will go to 0.
,w plot 3x
wraith daggerBOT
ornate cypress
Oh
kindred storm
Like if a was 3, you can see that it goes to 0 around 0.
clear ember
$a \cdot \frac{\log(1 + ax)}{ax}$ where $x \mapsto ax$
ornate cypress
kindred storm
Have you been taught L'Hospital yet?
ornate cypress
Reached here
kindred storm
,rccw
clear ember
then from your "identity", this is easily readable
ornate cypress
Have you been taught L'Hospital yet?
No, calculus has just been started last week
kindred storm
Oh, OK.
clear ember
yes you're almost done
fallen heath
!nohopital
fallen heath
same thing
kindred storm
You can multiply top and bottom by -b instead of b.
fallen heath
What about 1-bx
Do you realize the only change that happened was "+a" was replaced with "-b"
kindred storm
Then you'll have log(1 - bx)/(-bx).
ornate cypress
You can multiply top and bottom by -b instead of b.
That makes sense
ornate cypress
Do you realize the only change that happened was "+a" was replaced with "-b"
Got it
Thanks @fallen heath @kindred storm
kindred storm
,rccw
wraith daggerBOT
ornate cypress
Was 2 steps long and looked so intimidating
kindred storm
You're welcome.
cedar kilnBOT
@ornate cypress Has your question been resolved?
carmine otter
cedar kilnBOT
carmine otter
anyone can help with this pleas
frigid dust
!status
cedar kilnBOT
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
do you know hwo to transform it to reduced row echelon form?
carmine otter
do you know hwo to transform it to reduced row echelon form?
nope
how do i make the zeros?
frigid dust
you can add and subtract rows from each other
for example, if you subtract the first row 3 times from the second row you get
0x-4y-3z=10
kinda make sense?
fallen heath
frigid dust
<:sad:532803514892812288>
wrong choice?
oh, i see now
yes, do what arya said
ignore what i said
add row 1 and 3
cedar kilnBOT
@carmine otter Has your question been resolved?
carmine otter
@frigid dust like this?
frigid dust
<@946543471668379678> like this?
yes!
cedar kilnBOT
@carmine otter Has your question been resolved?
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peak prism
Hey guys any help with the following:
I need to find an example for a function g: $R \to R$ that satisfies the following conditions:
a. g is bounded, b. $lim_{x\to 0}g(x) doesn't exists$, c. $g(x) \neq 0 \forall x\neq 0$
my example was g(x) = sin(1/x)
the second question is given $f(x,y) = (x^2+y^2)g(x)g(y)$ now i need to show that $\lim_{(x,y) \to (0,0)} f(x,y)=0$ but the limits $\lim_{x\to 0}\lim_{y\to 0} f(x,y), \lim_{y\to 0}\lim_{x\to 0} f(x,y)$ don’t exists
wraith daggerBOT
st123
wraith daggerBOT
SWR
peak prism
your $g$ function is not defined at $x=0$
Yeah sorry, g(0) will just be 0
dull oxide
Hey guys any help with the following:
I need to find an example for a function g...
"but the limits $\lim{x\to 0}\lim{y\to 0} f(x,y), \lim{y\to 0}\lim{x\to 0} f(x,y)$"\
What?
wraith daggerBOT
SWR
cedar kilnBOT
@peak prism Has your question been resolved?
peak prism
Doesn’t exists, again sorry :/
cedar kilnBOT
@peak prism Has your question been resolved?
cedar kilnBOT
@peak prism Has your question been resolved?
weary thistle
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frigid dust
i think its quite clear that the integral diverges when yo ulook ath the graph
,w graph xcos(x^2) from x=0 to 100
wraith daggerBOT
weary thistle
I can't give an answer like that tho
gritty viper
i think its quite clear that the integral diverges when yo ulook ath the graph
I don't think it is
Use u-substitution instead
frigid dust
,w int xcos(x^2)dx from 0 to inf
wraith daggerBOT
gritty viper
,w int xcos(x^3) from 0 to inf
wraith daggerBOT
gritty viper
Not obvious, as I said
frigid dust
,w graph xcos(x^3) from 0 to 1000
wraith daggerBOT
frigid dust
this doesnt make sense but fair enough
gritty viper
It's true
slate lintel
this doesnt make sense but fair enough
i think the peaks get skinnier more quickly for this one. what a neat result, this is why we calculate analytically
frigid dust
,w int x cos(x^4)dx from 0 to inf
wraith daggerBOT
frigid dust
,w int xcos(x)dx from 0 to inf
wraith daggerBOT
frigid dust
if you u-sub u=x^2, then du=2xdx, dx=du/2x
then the integral becomes 1/2*int cos(u)du from 0 to inf
and that doesnt converge
but when the exponent goes higher, you get int cos(u)/u^something>0 du
which bounds the cos kinda
?
frigid dust
,w int x cos(x^(5/2))dx from 0 to inf
wraith daggerBOT
frigid dust
interesting
i think if the exponent is greater than 2, it converges
,w int xcos(x^(11/5))dx from 0 to inf
WA please 😭
gritty viper
Yes that is true
wraith daggerBOT
Requested by .bonk__
kindred storm
,w integral x cos(x^(11/5)) from 0 to infinity
Weirdly, it works on the actual website.
No, actually it doesn't.
frigid dust
i think cuz it reaches compute limit
kindred storm
Perhaps.
Strangely, it correctly interprets the query, showing the integral and everything, and then it blames the query.
cedar kilnBOT
@weary thistle Has your question been resolved?
zenith sedge
cedar kilnBOT
frigid dust
It needs to have travelled at least from t=0 to what you see in t=1
How many wavelengths is that?
zenith sedge
It needs to have travelled at least from t=0 to what you see in t=1
what does that mean?
zenith sedge
yea
zenith sedge
oh
zenith sedge
How many wavelengths is that?
4?
zenith sedge
8 mm
frigid dust
Because it can also always travel an extra wavelength and you cant tell
zenith sedge
im confused
coral jewel
it's helpful to label the crest
you know that each crest can only have one unique label; the same crest will never go to the same spot twice
frigid dust
it's helpful to label the crest
Cant it also move to the left? Thats the only thing i was wondering
Or is it assumed here it goes to the right
coral jewel
good point, i didn't consider that
but the usual convention is that it moves left to right
plus you can see the x-axis points towards the right
frigid dust
but the usual convention is that it moves left to right
Yeah thats what i figured too
coral jewel
we are not talking about the wavelength
frigid dust
why cant u just find the wavelength like this
This is not about finding the wavelength, that is indeed 4 mm
coral jewel
we are talking about the distance the crest travels in 1s
frigid dust
We are talking about this
zenith sedge
oh right
so the frequency?
cuz if we have frequency and wave lenght we can find velocity
frigid dust
You can also simply read off the velocity if you find the displacement
Since our given timestep is 1 second
And the distances are millimeters
If we know how much the string moved from t=0 to t=1 we already have our answer
zenith sedge
how do we get the displacement though?
frigid dust
so its just 3?
Remember the units
zenith sedge
mm/s
frigid dust
In this case, it mightve actually also been able to move left
So it might be -1mm/s
But i dont have the whole context of the question
cedar kilnBOT
cedar kilnBOT
Available help channel!
sudden kayak
How do I do this
Well
Oh hi lol
I just wanted to know if I did this right, this is for my geometry class
loud gyro
You found x = 6 right?
sudden kayak
Yes
loud gyro
And what does the question say about ED?
loud gyro
ED = x + 4 right?
sudden kayak
Yes
sudden kayak
Oh shoot wait I think I’ve might of accidentally changed the 3 to a 2
sudden kayak
Is it not?
loud gyro
np
take care next time reading the whole question again, to verify you havent made any wrong assumptions
sudden kayak
Yes sir 🫡
plucky owl
cedar kilnBOT
cedar kilnBOT
✅
sudden kayak
I think I might’ve solved it
I didn’t mistake the x this time
Is this right?
I put different ones this time
Wait nvm I solved it fr this time
.close
cedar kilnBOT
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Available help channel!
peak blade
can someone help me learn a topic for 10th grade pre calc? i got a quiz on the topic tmr and i got no idea how to do anything for it
peak blade
idk the name of the topic but it deals with stuff like "2sinx + 2 = cosx^2"
where you gotta use trigonometric identities to solve for x
dusk goblet
just post problems
peak blade
i already know all the trigonometric identities, like cosx^2 = 1 - sinx^2, and i already know how to isolate sinx and gettin it equal to zero, im just kinda shakey on getting the final answer using the unit circle
peak blade
just post problems
sure
thats sorta the extent to how hard the questions are gonna be
dusk goblet
,rotate
wraith daggerBOT
dusk goblet
which one
peak blade
uh idk like maybe 30 just to try the hardest?
dusk goblet
ok what have you tried
peak blade
tbh really only 21-24 and i didnt really "finish" them, just got sinx or tanx or wtv it was equal to zero
these arent hw btw, just practice problems
dusk goblet
ok then try 30 rn
dusk goblet
these arent hw btw, just practice problems
we can help you with hw
just not tests/quizzes
peak blade
yeah ik, my teacher posted these in case anyone didnt really understand it fully
dusk goblet
ok then try 30 rn
^
dusk goblet
if you’re going to write the ^2 make sure you write it before the x or outside of the parentheses
like sec^2x or (secx)^2
peak blade
(secx)^2(tanx)^2 = (tanx)^2
i cant divide both sides by tan right?
cuz i think i remember my teacher saying you lose possible answers that way
dusk goblet
no because what if tan is 0
peak blade
idk what you mean by that, but ill just follow the rule ig
dusk goblet
idk what you mean by that, but ill just follow the rule ig
you can’t divide by zero
you’d divide out potential solutions
peak blade
ohhhh shit yea cuz tan0 is just 0
dusk goblet
and tan(kpi) is 0
peak blade
ngl i think im stuck, you think you can give me a slight hint?
dusk goblet
well i didn’t even verify you did this correctly so i’ll work through it
$\sec^2(x) \tan^2(x) + 3\sec^2(x) - 2\sec^2(x) + 2 = 3$
wraith daggerBOT
knief
dusk goblet
$\sec^2(x)(\tan^2(x) + 1) = 1$
wraith daggerBOT
knief
dusk goblet
$\sec^4(x) = 1$
wraith daggerBOT
knief
dusk goblet
(secx^2)(tanx^2) + 3secx^2 = 1 + 2secx^2
how did you get this
peak blade
oh wait im stupid, i read the - tanx^2 as secx^2
dusk goblet
happens
peak blade
alr lemme retry, i didnt rlly pay attention to ur work cuz it was coming so fast lol
yea ngl idk how to do this
im gonna just check over your work
dusk goblet
im gonna just check over your work
ask questions if you get confused
about what i did
peak blade
ok
peak blade
**knief**
how did you get rid of everything else while simplifying the whole right side to just 1
dusk goblet
**knief**
to get the left hand side here^
after that i combined the 3sec^2-2sec^2 into just sec^2
and i also moved the 2 over to the right side
hence how we got a 1
3-2
then from there i factored out sec^2
and then finally rewrote tan^2+1 = sec^2
peak blade
gimme a sec to understand all this
dusk goblet
@peak blade what town hall are you
peak blade
<@927080003122892861> what town hall are you
th 12 i think
dusk goblet
do you understand what i did
peak blade
kinda
i got up to here trying to recreate what you did
(secx^2)(tanx^2) + secx^2 = 1
peak blade
the sec and tan in parathesis are being multiplied to eachother tho
peak blade
i don't understand "ab+a = ab + a(1) = a(b+1)" at all, is that some formula?
peak blade
oh like algebra 1 shit??
dusk goblet
$(\sec^2 x - 1)(\sec^2 x + 1) = 0$
wraith daggerBOT
knief
dusk goblet
dont u gotta like forth root the one tho now?
yes or do this
$(\sec x - 1)(\sec x + 1)(\sec^2 x + 1) = 0$
wraith daggerBOT
knief
dusk goblet
assuming we don’t want imaginary solutions we just have sec x = +- 1
peak blade
yeah this is the part i get shakey on
im normally pretty good on getting to this part, where secx equals something
but i have no idea how getting the final answer works
winter moss
can you use calculators or nah?
peak blade
not sure, if its some absurd calculation, probably, but if its just something that uses the radian degree value chart or the unit circle, probably not
dusk goblet
can you use calculators or nah?
this is horrible advice
peak blade
he expects us to memorize those charts
wraith daggerBOT
knief
winter moss
this is horrible advice
??? i just wanted to know what they had access to
dusk goblet
??? i just wanted to know what they had access to
doesn’t matter
winter moss
doesn’t matter
yea ig
peak blade
**knief**
why bother switching to cosine when i can just look up secant values on the chart
winter moss
why bother switching to cosine when i can just look up secant values on the char...
cause sec = 1/cos
so its easier to only memorize sin and cos
dusk goblet
why bother switching to cosine when i can just look up secant values on the char...
because who memorized shit for sec
just memorize what you know for sin cos and tan
winter moss
then solve for tan, sec and cosec
dusk goblet
then use the simple identities
peak blade
dusk goblet
why bother switching to cosine when i can just look up secant values on the char...
don’t rely on charts lol
winter moss
just memorize what you know for sin cos and tan
why memorize tan? cant you just solve for tan?
peak blade
why memorize tan? cant you just solve for tan?
oh yea hell nah, im not smart enough for that lmao
im barely keeping my 90 in this class
winter moss
oh yea hell nah, im not smart enough for that lmao
tan = sin/cos
peak blade
still trips me up
winter moss
im barely keeping my 90 in this class
u want that 100 dont you
dusk goblet
but i didn’t find it that hard to memorize tan(pi/6) = 1/sqrt(3) and tan(pi/3) = sqrt(3)
dusk goblet
oh yea hell nah, im not smart enough for that lmao
nothing to do with intelligence
peak blade
u want that 100 dont you
😭😭 ill be lucky if i keep my 90, its legit a 89.7 right now
dusk goblet
you have to memorize like 5 things?
winter moss
nothing to do with intelligence
some people have an easier time memorizing than others
winter moss
you have to memorize like 5 things?
yea thats true too lol
peak blade
nothing to do with intelligence
idk i get tripped up with lots of division with fractions and stuff
that was all 6th grade for me, around the time for covid
winter moss
here
dusk goblet
some people have an easier time memorizing than others
anyone can memorize 5 things
winter moss
if you memorize this ur all set
peak blade
some people have an easier time memorizing than others
charts and maps are easy for me to remember, formulas and facts not rlly
dusk goblet
yes pretty much but you don’t even need to memorize the multiples of 90 so long as you understand a few things
winter moss
if you wanna make it easier you can try looking at the graphs or circle
winter moss
charts and maps are easy for me to remember, formulas and facts not rlly
same lol, i remembered all the tirgs graphs rather than the numbers XD
winter moss
also how does the +2piN or +piN work
a full circle is 2pi
dusk goblet
they repeat
peak blade
right but when do i use them
like when do i add a full period or half a period or none
winter moss
like when do i add a full period or half a period or none
none is when ur within a specific domain
full period is without a domain
and half period is circumstantial
peak blade
ok… i get the domain and without domain part
what circumstance would i use half period
winter moss
well cant rlly think of one on the top of my head
peak blade
i think i remember somewhat
of a visualization my teacher did
its like imagine a sin graph
winter moss
yea but thats only if its sin^2
in which negative/postive wouldnt matter
and you could use +pin
peak blade
still dont understand that
like
i think i get how to get at least one answer atp
its just the multiple answers are fcking with me
winter moss
alr we getting off track lets go back to the question
winter moss
**knief**
here
how can you simplify this equation
$(\sec^2 x - 1)(\sec^2 x + 1) = 0$
wraith daggerBOT
Kingenbu
peak blade
(secx - 1)(secx + 1) (secx + 1) (secx + 1)?
wraith daggerBOT
Kingenbu
winter moss
simplify thios
dusk goblet
what circumstance would i use half period
tan/cot have a period of pi
dusk goblet
simplify thios
already did mate
peak blade
simplify thios
(secx -1)(secx + 1) difference of squares right?
dusk goblet
(secx - 1)(secx + 1) (secx + 1) (secx + 1)?
no
winter moss
(secx -1)(secx + 1) difference of squares right?
why cant you use it vs the other half?
dusk goblet
sec^2 + 1 ≠ (sec + 1)^2
winter moss
already did mate
yea but clearly he didnt get it lol
winter moss
tan/cot have a period of pi
thats it ty, idk why that skipped my mind
peak blade
tan/cot have a period of pi
oh so only when its cot or tan
dusk goblet
oh so only when its cot or tan
mhm
winter moss
oh so only when its cot or tan
yea back to the difference of squares
peak blade
yea back to the difference of squares
yes capn
winter moss
do you understand why you cant use the same rule on both parts?
winter moss
yes
winter moss
yup
peak blade
x2+1
winter moss
its the "DIFFERENCE" of squares
winter moss
yea
it has to be one square
minus another square
only then can you apply that rule
$(\sec^2 x - 1)(\sec^2 x + 1) = 0$
wraith daggerBOT
Kingenbu
winter moss
so simplify this again
peak blade
so if i cant simplify it that way, and its just (secx - 1) (secx + 1) (secx^2 + 1), dont i have to square root the 1 thats with the secx^2
winter moss
yes but think about it
winter moss
take it slow, no need to rush
no
take it slow
now that you have 3 brackets
that multiply to 0
how else can you write this?
peak blade
oh yea cuz one is squared
idk, you want me to write them all individually equal to zero?
peak blade
oh fck bruh imaginary numbers???
cuz when i do secx2 + 1 = 0 to secx2 = -1 and sqrt the negative one, does that give me “i * sqrt1”
peak blade
now can any squared number be negative?
no
winter moss
right
so can you have an imaginary numbers as an answer?
obv yes, but im asking from your point in class rn
peak blade
i mean
idk i trust you guys have gotten me to this correctly so far and i somewhat trust my own work getting me this far
but like istg hes never mentioned imaginary numbers at all this year and i dont think he’d give us a test on smth we havent learned yet
peak blade
alright
winter moss
secx + 1 = 0
secx - 1 = 0
remember that secx = 1/cosx
can you isolate for cos x in both equations?
winter moss
so what are the two new equations
peak blade
im at “1/cosx + 1 = 0” “1/cosx - 1 = 0”
winter moss
yes but isolate for cos
peak blade
oh isolate
winter moss
so make it cosx = ...
then after that you just use what you memorized, or the chart if u want to, to find out what x is
peak blade
oh its the same thing from secant
winter moss
and dont forget the +2pin
winter moss
oh its the same thing from secant
yea i said cos cause cos is easier to memorize
peak blade
cosx +-1 = 0
yeah, technically not the same thing ig cuz if it wasnt plus or minus the answers individually just flipped
winter moss
so x = 0, 180 or 0, pi
winter moss
yeah, technically not the same thing ig cuz if it wasnt plus or minus the answer...
yea
but anyways do you get it now?
peak blade
so my answer would be “0 + 2piN, pi + 2piN”?
winter moss
i made it 🙏🙏🙏
is it right?
peak blade
oh i dont have an answer key lol
but i feel like i understand it way more so im pretty confident thats right
thanks both of yall
damn ive been in here for over an hour
winter moss
damn ive been in here for over an hour
yea math takes time lol
winter moss
but i feel like i understand it way more so im pretty confident thats right
just checked myself
its right
regal moth
yea math takes time lol
could you play me in chess?
winter moss
dont forget to close
peak blade
im better with languages, math is not my area of expertise lol
winter moss
could you play me in chess?
sure?
peak blade
dont forget to close
how do i do that
winter moss
.close
peak blade
.close
cedar kilnBOT
cedar kilnBOT
Available help channel!
versed walrus
pls help
versed walrus
.close
cedar kilnBOT
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latent hamlet
Why lim x->0+ li(ix)=ipi? I don't understand li(x) analytic continuation
dire geode
What's li
dire geode
Try one of the series expansions
https://en.m.wikipedia.org/wiki/Logarithmic_integral_function
cedar kilnBOT
@latent hamlet Has your question been resolved?
cedar kilnBOT
@latent hamlet Has your question been resolved?
cedar kilnBOT
@latent hamlet Has your question been resolved?
cedar kilnBOT
cedar kilnBOT
Available help channel!
raw hollow
I know the answer is a because I know the value of f(x) is pi/2 when x = pi/2 and when I put pi/2 in place of x A is the only option where it's pi/2.
raw hollow
But I can only say this because I know the value of f(x) at pi/2
How would I solve this normally if I couldn't just calculate it?
I think I need to use taylor expansion but I don't know how to use it in this case
cedar kilnBOT
@raw hollow Has your question been resolved?
dawn junco
I think I need to use taylor expansion but I don't know how to use it in this ca...
You'd have to be able to evaluate the function itself + its derivatives at x=pi/2 if you want the taylor expansion anyway
dawn junco
I know the answer is a because I know the value of f(x) is pi/2 when x = pi/2 an...
What about C tho ? It's also equal to pi/2 at x=pi/2
raw hollow
What about C tho ? It's also equal to pi/2 at x=pi/2
oh ye ur right
the answer key says a tho
raw hollow
You'd have to be able to evaluate the function itself + its derivatives at x=pi/...
and how do I do that?
dawn junco
What's your issue here with taylor expansions ?