#help-13
1 messages · Page 34 of 1
Closed by @tiny socket
Use .reopen if this was a mistake.
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 the graph correct?
the first "condition" or piece?
ah ok
I think you mistaken that as 1/2 x
what should it be
oooops
If I were to rewrite it
Closed by @glacial locust
Use .reopen if this was a mistake.
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 need explanation how to do this math
@reef glacier Has your question been resolved?
explain
Closed due to timeout
Use .reopen if this was a mistake.
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 by @plucky dagger
Use .reopen if this was a mistake.
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 I have no idea how to do question 15 can someone help me
@zenith ridge Has your question been resolved?
what is the formula for compound interest
Closed due to timeout
Use .reopen if this was a mistake.
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've been staring at this for 30 min and cannot figure out where
(1,1,0) and (-2,0,1) comes from
any1 have any idea?
look where $t_1$ and $t_2$ are in the equation
Jigglyproff
and remember that the vertices stand for (x,y,z)
Closed by @coral valley
Use .reopen if this was a mistake.
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, can someone help me solve this problem? I know it can be solved using Laplace transform, but I don't know how to start
There is a relationship that links the Laplace transform with derivatives
@graceful hinge Has your question been resolved?
Closed by @graceful hinge
Use .reopen if this was a mistake.
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.
What formulas do i use for 7
I got 7i)
Hey guys, I have really been enjoying Discovery Pre-Calculus as a free EdX course with the Uni of Texas at Austin - does anyone know of any similar courses where the emphasis is on problem-based learning and exploration, perhaps on statistics?
stats is great but you wont get very far in stats without knowledge about probability and more calculus
You should first find the slope of the both lines
Cool - are there any nice courses on probability that you know about?
Then use tanΘ = m2 - m1/1 + (m1m2) to find the angle
could you open your own channel so we can discuss this more
That's correct
I meant the point
Ermmm i forgot
You can solve both the equations to find x and y
To find a point (x,y)
That is the intersection coordinate
Kk
That's the formula for the perpendicular distance from a point
We have been asked to find the distance from the origin to the point of intersection
Ayyy
Now use the distance formula
Origin is 0,0
And you have the point of intersection -5,3
How do i get the other point x2 y2
We already have two points
Oh kk
Let me draw the thing to make you understand
,rotate
Oh yeah this is correct
Also tysm for helping me
Np
This is just an example
The two lines l1 and l2 meet at point (x,y) and d is the distance from origin
Kk
L and k
Yes
Yes
Lemme try i dont think so
If we have 3x + y = -12
Put x = 0 and solve for y for first time and then do y = 0 and solve for x to find the two points and join the two points
To get the line
Same process for x + 2y = 1
Is l= (-4,-12)
K= (1,1/2)
0,-12 and -4,0 for L
Okay
L = (0,-12) (-4,0)
K= (1,0) (0,1/2)
Yes
Kk
Is it (0,-12 ) (-4,0) (0,1/2) idk how to find which points to use
Ohhh
Its not 0,1/2 since they dont meet at x - axis
We look at points at x axis
And the point of intersection
Okay
Then we make 1 (0,0)
Its not 0,-12 its -5,3
Kk
Wdym
I dont understand can you explain what exactly you mean
Its finee dw
-1 not +1 at the top
Oop
Wait i did it wrong
Then the 1/2 | x1y2 - x2y1| right?
Hmmm
And i dont think that works
We only need three points for a triangle
Yep
Gimme a sec
Sure
So the formula i was using worked
The answers at. back of the book had this aswell
Sure
The one above this part?
This one
Kk
The 4th part
How do i do part 5
I was confused since i later realized the line l is 3x + y = -12
Ohhh
Do you know the formula for the perpendicular distance
Hows that
By multiplying √10 to numerator and denominator
Np
And i think the triangle one is correct
You should ask your teacher
Ye i will
About it too
Im gonna go cya have an amazing day
Closed by @loud wyvern
Use .reopen if this was a mistake.
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.
which area should be shaded?
as in, what is the region that the expression asks for?
@molten wave Has your question been resolved?
Closed by @molten wave
Use .reopen if this was a mistake.
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 we solve for the volume of this solid of revolution?
Revolved around x = -2?
I’m not sure, I think so
In this section, the second of two sections devoted to finding the volume of a solid of revolution, we will look at the method of cylinders/shells to find the volume of the object we get by rotating a region bounded by two curves (one of which may be the x or y-axis) around a vertical or horizontal axis of rotation.
Closed by @violet mountain
Use .reopen if this was a mistake.
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.
ok
That’s what I thought too but if you had to show work, what would you write?
Maybe just say cos(theta) = 1/sec(theta)
then plug in 6/5
even that's kinda overkill though lol
Dope thanks
np 👍
@pine estuary Has your question been resolved?
Closed by @pine estuary
Use .reopen if this was a mistake.
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
Well, find the ratio of sugar to water for both
i don’t under stand the lesson this is my first time doing it
I don't know what the RACE strategy is. Do you know about it?
Restate the question in the form of a statement.
Aswer the question.
Cite the evidence.
Explain the answer.
The question is Which season uses a greater sugar to water ratio? How could you rephrase that question into a statement?
@cosmic bramble Has your question been resolved?
I don’t need help with RACE i need need a good enough answer with a explanation
<@&286206848099549185>
Have you come up with some type of answer yet?
Yes
Let's see it and we can offer suggestions for improvement.
How did you come up with 3/2 divided by 2?
$\frac{3}{2} \text{ divided by } 2 = \frac{\frac{3}{2}}{2} = \frac{3}{2} \times \frac{1}{2} = \frac{3}{4}$
Kookiemon
Closed by @cosmic bramble
Use .reopen if this was a mistake.
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.
Solve the system. You can get a lot of mileage doing line 2 - line 1, for example
so itll be the difference equal to 0?
λ - λ is equal to 0
yeah so y = x
then we can see that 2x+z=100000
what do I do now?
@upper abyss
<@&286206848099549185>
@eager pier Has your question been resolved?
.close
Closed by @eager pier
Use .reopen if this was a mistake.
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 find antidervative of this
and these
for the first one this is whta solotuion say
but i dont understand why the g'(x) dissapears
@fringe anvil Has your question been resolved?
Closed by @fringe anvil
Use .reopen if this was a mistake.
ty
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 calculate the near and far plane of a camera
tbh i dont even know what they heck they do or what they are but i need them to project 3d point to 2d
@dim copper Has your question been resolved?
Not really a math question, isn't the near and far planes the boundary of what's to be rendered by computer graphics?
@dim copper Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
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 doing anything wrong. The answer is given by a double integral with integrand 0, over the rectangle.
This is, of course, 0.
Yes. Umbra raises a good point that this is naturally 0 by the fundamental theorem of vector calculus. Using Green's to get the result is weird.
But whatevs!
@lone portal Has your question been resolved?
Closed by @lone portal
Use .reopen if this was a mistake.
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.
,rotate
Just want to know is c) Loga (2)(3xy)-loga(5)(z)
no, because only y is squared
Z⁵ on bottom
-5log(z) is correct
Where'd a go
im lazy and there's no other bases in the question :p
-5log_{a}(z) it is
oh actually now that i look at it, that's not the correct application of log laws in your answer
IV
rule 3 indicates you should bring the exponent outside and in front of the log
Closed by @tender spire
Use .reopen if this was a mistake.
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.
so for polynomial graphing with multiplicity how do you tell the multiplicity of a y intercept like how can i tell if i should touch or cross on the y int
usually you won't worry about a y-intercept's multiplicity 
(assuming your polynomials have the form y=f(x) for some function of x)
are the y-int always going to cross and not touch/swoop in graphing then?
if it swoops then for some value of x you get 2 different y values
then you don't have a function but instead a relation
Closed by @strong silo
Use .reopen if this was a mistake.
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.
what am i do wrong
have you got working??
looks like you raised a 1 to a common denom
$a_n=(3a_{n-2}) \cdot (2a_{n-1})$
Clarkie
in the third case , $a_3$
Clarkie
okok
your n value is 3,
so you get something like looks like $a_3=(3a_{1}) \cdot (2a_{2})$
Clarkie
Closed by @warm palm
Use .reopen if this was a mistake.
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 to solve this ?
id imagine you could just write cosec(a+ib) = 1/sin(a+ib)
then expand with the sin addition formula using the givens and it should just like pop out
okay trying it
Lol
haha that’s just unsightly typesetting
@violet silo Has your question been resolved?
Closed by @violet silo
Use .reopen if this was a mistake.
What's the difference between cosh and cosx tho
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.
This is the given limit, I'm testing if it's continuous or not
x->5?
Now I can do the whole right and left hand limit thing to do it
Or just substitute x=π
oh pi
Oh yes
$\lim_{x \to \pi} (\sin x + \cos x)$
DerpZ
do you know the requirements for a limit to be continuous
f is continuous at x if ...
yuo do x=pi when you are trying to evaluate the limit
but in this case, you are trying to see if the limit is continuous
For a limit to be continuous?
The book did this for a few provlems
Yeah
wait, you want to prove continuity?
Shit I'm not expressing my problem right
Is there something wrong with doing this, other than it being taking longer to solve
are you trying to prove continuity or solve the limit?
I'm trying to prove continuity of the function (sinx + cosx) at x=π
if you want to find the limit you can just plug in sin(pi)+cos(pi)
Yes
ok so let epsilon > 0 be arbitrary
Alright
so now you want the delta such that |x-pi| < delta
implies
|f(x)-f(pi)|<eps
where f(x) = sinx+cosx
I'm not getting
Pre calc
yea
So
i have trouble with limits
Is sin(x) + cos(x) defined for the entire domain?
its not given
Okay uh
R
nope
R
great
is the domain
nope
yes
yes but that doesnt sort the problem i have tho
its more to do with limits i think
Oh ABSOLUTE value
I have no trouble understanding how they did this part othe than that how they just substituted x=π in the limit. I thought continuity required LHL=RHL=f(π)
No not the function itself
The limit
I was proving continuity using this method
I hope it's legible
this is just for the right hand limit, similar for lhl, i can do that too if you want
@gilded elm sorry for the ping but help
I'm confused on what you are confused about
oh
The solution seems perfectly reasonable to me
i see
as in
can it be done via this way
but notice why this works
this is one of them
wdym defined
defined meaning (in a simple way) that
you can evaluate that
for example 1/0 is not defined
oh yes
say you want to evaluate $\lim_{x \to 0} 1/x$. Then you can't just calculate 1/x
DerpZ
This is the method i used in my "solution"
Ah ok
Yeah your method works
So we cant substitute where there are constraints
You can only substitute when the limit is defined
I.e. you can only compute the limit when it's defined
Wdym by the limit is defined
When the functions defined right?
At the value where x is tending to?
Yes
in an intuitive way if you imagine the graph
you can see it's shooting off to infinity
Yup
so that limit isn't defined
I see
but lim at x=pi of sinx is defined
And for cos x too so we can substitute it
Correct
Got it
So if you visualize the graph of the function
Limits are really confusing haha
lmao wait till you get to real analysis
True
some of the functions are even weirder
Yea no I'm good lol
Alright
Thanks a bunch
.close
Closed by @glacial locust
Use .reopen if this was a mistake.
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.
Y = (3x/2) - 2
State the rise of the line if the run is: 2, 4, 7
State the run of the line if the rise is: 3, 9, 4
Closed by @brave frost
Use .reopen if this was a mistake.

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.
Slove in Laplace transform
@exotic field Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
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.
so ice is at temp 0C
That's wt confusing I don't know the temperature of ice lets assume it to be as 0°C
well ice is 0C u dont have to assume it
Ok then..
Q=Lm
Heat gained by water ?
S
in turning to water at 0degC
S
S
it wont just stop at 0degC
Yep
by S do u mean yes?
when does the heat exchange stop?
When the water and ice both become same temperature
T
Ok
Yep
and the water in the beaker is what must give out the energy required for all of this
so the water in the beaker starts at 50degC
and cools down to T
So it's Q = mct
the heat the water in the beaker loses in cooling down from 50deg to T, is what the ice cube takes to melt into water at 0deg + the energy that water at 0deg takes to heat up to T
now u must be able to write an eqn
Heat energy gained by ice at 0°C to become 0°C of water then to T°C of water = Heat energy lost by water to reach T°C from 50°C
Is it correct?
@lusty grotto what's the equation?
yeh
this is correct
200×4.2×(50-T)=42000-840T
Amt of heat lost by water
yes
Amt of heat gained when 40g of ice at 0 °C converts into 0 ° C water
40×336=13440
yes
Now 0°C to T°C water
yes
yes
After this ?
put those values here
13440+168T=42000-840T
Is this correct
yes
Yaa got it
👍
Closed by @nocturne oriole
Use .reopen if this was a mistake.
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 have to prove this for any natural m>1.
I tried to use induction, now I'm stuck tried to prove this
try converting it into exponential form
Closed by @high marten
Use .reopen if this was a mistake.
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.
having trouble trying to prove this identity
Ur numerator looks wrong
Shud be sin(-x) at the end
Yea and then youre done
Did I get one of the rules wrong?
Yea
I remember doing that
Wait some seconds
The last one is cos C - cos D = 2 sin((C+D)/2)sin((D-C)/2)
oh explains why its wrong, appreciate the help <3
.close
Closed by @proud monolith
Use .reopen if this was a mistake.
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.
@meager flare Has your question been resolved?
maybe something like a_n+2 = 5a_n+1 - 6a_n + 2n(-2)^n
n = 0
a_2 = 0
everything is 0
wait that cant be right lol
idk im bad at seq someone else can help
don't do people's work for them
👀 sorry idk
@meager flare Has your question been resolved?
@meager flare Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
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, how would I solve for A and B if
A*cos(x)^2 + B*cos(x) - 1 = 0
Where two possible values of x are (pi/3) and (5pi/3)
Thanks
quadratic formula
yea I tried that and it didn't work
did my calculator just break?
I guess so then
show your work
so I would solve for A then substitute that back into the quadratic formula to solve for B?
$\cos(x) = \frac{-B \pm \sqrt{B^2 - 4A(1)}}{2A}$
riemann
now plug your two values and get 2 equations for 2 unknowns
follows from your equation
if it helps, rewrite your equation using the variable
$y = \cos(x)$
riemann
ok thanks
I thought quadratic formula solves directly for x but I guess not
.close
Closed by @maiden cloak
Use .reopen if this was a mistake.
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 would I be able to equate this answer to [(-2)sqrt3]/3?
I tried getting it down to secx, but without it being a special angle I can’t equate it further
is it 7pi/6 insid the brackets on the last line
Yea
if you can give us the original question
7π/6 is a special angle, no?
Basically the original question was to sub in -pi into g(x)/f(x), where f(x) = sin(x-pi/6) and g(x) = tan(x-pi/6)
I meant special angle as in like this special triangle
It's on the unit circle
.
If you know which trig functions are positive/negative in the 3rd quadrant, you can just use π/6
Then apply the right sign
Ahhh okay I think that makes sense
Let me try it
Got it
Thank you all so much for the help ❤️
@lapis mantle Has your question been resolved?
Closed by @lapis mantle
Use .reopen if this was a mistake.
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 duration of different electronic components of a fabric follows a normal distribution of N(500,σ). How much is the value of σ, if the probability of having an electric component of a duration between 450 and 550 is 0,75?"
- I tried to solve this probability exercise but I keep getting stuck at the end and I can't find the value of "σ". The exercise says that the solution is "σ=43,48" , but I can't find a way to get there, I don't really know how to continue or solve this, I tried to search this online but I found no sources or resolutions to this problem.
imagine the probability density function of the normal distribution
it looks somewhat like this
Let F^-1 be the inverse cdf of the normal distribution
F^-1(0.125) is the z-score corresponding to 450 in your distribution
but also, the z-score corresponding to 450 is calculated as (450-500)/sigma
and you can simply set these equal and solve
or another way of looking at is
F((450-500)/sigma) = 0.125
and solve for sigma
@dapper imp Has your question been resolved?
I see now, the drawing makes it clearer, thank you
Closed by @dapper imp
Use .reopen if this was a mistake.
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 anyone please explain why in the integrals there is npix/L by cos
It looks like we're missing context. Was anything before this? What was the question?
That doesn’t make sense
Could you please elaborate
Idk why it’s in the numerator
I am really confused by the integration by parts here
what doesn't make sense? i don't think it should that clear until you do or see the computation, anyway
like unless you can find an antiderivative of this just in your head
you kinda just have to compute it lol
What do you mean?
As in here
This is what I am getting it doesn’t look the same
$\int x \sin\left(\frac{n\pi x}{L}\right) dx$
oops didn't mean to reply
💜𝓁𝒶𝓎𝓁𝒶💜
this is something to compute
and you can do it with integration by parts i imagine
Yes that’s what I tried doing
probably made an error then
:c
on your side i mean
OR it's the same thing but in a different form, or just not done yet
.close
Closed by @earnest pendant
Use .reopen if this was a mistake.
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.
any good online calculators for parametric equation to cartesian equation
i dont have time to do all of these by hand
cant find one
Nope, sorry! If you're not getting an answer it's because we don't do that stuff here. If you don't have enough time, then come back when you do. Sorry that was not the answer you expected, it's the best you'll get on this server for questions like this :/
its ok i get it
@crimson sedge Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
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.
this says that the second derivative being 0 makes the theorem inclusive
so when does the second derivative being 0 indicate an inflection point
or was that just some false thing i learned during high school?
using x^3 as an example theorem 16 checks out because 3rd derivative would be the first non vanishing derivative at x=0
and k would be odd so it's a point of inflection at 0
that's insufficient and the reason that's why you need the generalization
inflection point => second derivative = 0, but the other direction doesn't work, consider y=x^4
ahh yea i see true for the first derivative and how it equaling 0 doesn't imply a local min/max
also
pretty sure that actually does hold
in theorem 16 there's a part that says suppose the k+1 derivative of f exists, i don't understand the relevance of it
it can be a point of inflection but the converse is true that a min/max => derivative = 0 , it was something they pointed out in this pdf
oh right i misread 
oh hey riemann
i guess you can construct a grotesque counterexample to abuse the lack a of continuous derivative but i cant do it off the top of my head
Closed by @wild stone
Use .reopen if this was a mistake.
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 chi square test technically always a onesided test so you never have to multiply the p-value by 2?
@hidden radish Has your question been resolved?
@hidden radish Has your question been resolved?
@hidden radish Has your question been resolved?
@hidden radish Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
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 i find derivative of arcsec and arccosec ?
i found arcsec like that
You can derive them using the derivative of the inverse
Unless you are talking about how to apply the formulas you know of those
what is my mistake ?
this is derivative of arcsec
i would like to apply formula
i applied this formulas
but something wrong
How comes you did $\frac{8}{1 \cos^{-1}(5v)}$ if you don't mind me asking?
chartbit
No that's not how it works
oh
[
\arcsec(x) = \arccos(\frac{1}{x})
] is the correct statement
♡LexQa♡
when x is approximately 7.07891760755
That's effectively saying arcsec = sec
arc = 1
arcsec is arcsec
wow
,w plot arcsec(x)
,w plot 1/(cos(x))
and dividing by arc gives us sec = sec
ah yes ofc
Mind you, thought the original thing written was arcsec = 1/arccos as well 
Layla inventing the Laylan lemma I see
anyway arcsin is arcsin, arccos is arccos, arcwhatever is arcwhatever
no rewriting them as 1/sin or 1/cos or 1/whatever
the confusion is some people write cos^{-1} for arccos or whatever
the confusion is probably more that people think sin(x) means some symbol sin multiplied by x
which is just like completely not what it is
huhh really
i found 40/(u^2)(1-25u^2)^1/2
i thought everyone knows its s times i times n times x

i found [40/(u^2)(1-25u^2)^1/2
]
for c)?
its wrong why
How did you find it?
firstful i made
yes
i made -1 *8 *-5u^2/(1-25u^2)^(1/2)
[
i made -1 *8 *-5u^2/(1-25u^2)^(1/2)
]
i made
[
-1 *8 *-5u^2/(1-25u^2)^(1/2)
]
$$
- \frac{ (1)\cdot (-8) \cdot 5u^2}{(1-25u^2)^{1/2}}
$$
not 18 -8 it was 1*-8
where are you getting the 5u^2 from
Keep telling me if I'm typesetting what you mean?
no 1-8 inside the dominator
Hmm but why?
numerator sorry
8arccos(1/5u)
\dv looks better dc 
Hmmm, that's better, but not quite there I think?
Though of course, they do give you the derivative for arcsec right there anyway, why not just use it?
[
\dv{x} >>> \frac{d}{dx}
]
♡LexQa♡
in exam i cannot regonize all formulas i just tried solve with arcosx derivative
i dont like the upright d
is it possible to solve with arccosx derivative
...anyways, believe what you should be getting is something like
$$
-\frac{8 \cdot (-1/5u^{2})}{\sqrt{1 - (1/5u)^{2}}}
$$
no?
chartbit
Before simplification
and
At least what I've typeset doesn't seem to match what you have...
yes it doesnt
Do you agree though that this is correct?
im stuck at third step
This is my work but i cannot understand why my answer not correct
@cerulean sail
,w diff 8*arcsec(5x)
How did you input it - did you use u's rather than x's?
This is equivalent btw
Actually ignore
Hmmm, I don't know, what you have at the end should be right, unless I'm missing something clear...
Might be the way you're typing it in, maybe?
i mean i dont understand third step on this picture
Oh they're just weirdos for that 
?
They've done some weird form there - it's still the same at the end of the day, but I don't even see why they won't accept yours
...they probably have some formula they're using, I'm guessing?
i didnt send my answesrs yet
,w diff arcsec(x)
not same
Ah, they're taking this to be the "formula", strange people there
The one they have here is better looking imo
they re bastrds they re manipulating students not fair
Actually strange people they have (and tbh I don't even see why Wolfram writes it like that either) 
Makes no sense to me, this is a more simple form
Might be that they're taking this one I guess... 
Yeah, it's the same thing at the end of the day - personally I would rather accept your version than theirs, but that's just me(!)
@fiery berry Has your question been resolved?
Closed due to timeout
Use .reopen if this was a mistake.
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.
@quartz vale Has your question been resolved?
Closed by @quartz vale
Use .reopen if this was a mistake.
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.
@austere zealot hey sry last question
Yes?
So I am still struggling with the objective function
I have this now:
But this is just revenue
But I want to maximise the profit
this would be the profit one for book 1 (I think)
I believe that is correct.
You just need to calculate that value for all 5 books and sum it all up. I presume you know how to get Excel to find optimal solutions?
Yes I do
So the objective function
would be:
- and then the same but for book 2,3,4, and 5?
I believe so.