#help-33
1 messages · Page 142 of 1
your expression P(t) is correct
My online notes only show examples of them finding expressions where the base was e. Is there a way to find an expression using e?
2 is the same as e^(ln(2))
technically 500(2)^(t/15) is a totally accurate "exponential model"
if they don't tell you it has to include e then it might be unnecessary, but you can rewrite P(t) as 500 * (e^ln(2))^(t/15) = 500e^(t * ln(2) / 15)
,w 500(2)^(87/15)
Closed by @topaz tide
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 help with this:
integration
more specifically when integrating to find distance, make sure to use absolute value since distance cant be negative
absolute value of the part where the integral function is negative
This is helpful but class was canceled at my uni due to a massive power outage so I was never taught how to actually do this.
So I dont even know the first step or how to do it
are you familiar with power rule?
Do I integrate the v(t) equation?
yeah
yep
sweet thank you so much.
well yea for displacement at least
^
so you might need to split the bounds up depending on whether the function goes negative or not
for example: if the integral function is negative on (4,7) you would take ( f(4) - f(2) ) + | f(7) - f(4) |
does that make sense
ok wait let me graph it
may not respond for a bit but thank you so much I have to run an errand
if you could dm me a detailed explanation or walkthrough of how to do the second part that would be so helpful
@timid 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.
am i tweaking
it depends on t, not x
and for the second part, look at what it actually wants
for example, look at the units
they don't want the amount of bacteria
OH
yeah i misread that as well at first
Closed by @dense hemlock
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.
Isolate sin(theta) using algebra, then use arcsin (presumably a calculator if you're allowed to) to solve for theta
.close
@tall sun Has your question been resolved?
.close
Closed by @tall sun
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 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.
What does the d and y axis label mean
@rocky nexus Has your question been resolved?
<@&286206848099549185>
No idea about these notations, do you need any help in understanding how we can plot it?
.close
Closed by @rocky nexus
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.
Calc 1:
I am dealing with using the chain formula, but I am stuck on this one
It's got a lot going on and I get the idea, but its confusing me.
Specifically with finding the derivative of 4^cos(x^6)-1.
Chat GPT says I have to use ln(4) but I have no idea why.
So if we want to differentiate 4^x how do we do it?
xa^x-1
Ah no not quite
So we are differentiating with respect to x
Do you know that the differential of e^x is e^x ?
oh right I was thinking backwards like x^a
Yeah, common mistake, I do it all the time
right yeah e^x just = e^x I understand that
So if we want to do a^x, well we don’t really know what it is off the top of our heads
So we want to write a in terms of e
So a = e ( ln (a))
oh interesting
Which seems a bit weird until you do a^x = e( ln(a) * x )
So then you just differentiate e( ln(a) *x ) which is by chain rule, ln(a) * e( ln(a) *x )
Hope this helps 🙂
😵💫
So it’s e^u * du / dx
Where u = ln (a) * x
You’ll have to work through this example yourself to get a proper understanding
Than hopefully your question will make sense
Yeah I appreciate it. Just super confusing
For sure
@mortal lintel 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.
Number 4 is confusing me
This is the lines graphed
Idk what it is asking me or what a lattice point is
How am I supposed to divide this up into 7 regions?
Lattice points are points (a,b) where both a and b are integers.
Can they be anywhere?
Yes, but here they are only concerned with those inside the triangle
Yes, it's just how the lines delimit the triangle.
The triangle itself isn't split in 7 regions, it is one of htem
Nvm
OHH
So how am I supposed to calculate the lattic points?
Am I able to calculate it or do I have to use the graph?
They aren’t integers
I’ll get it for u
(1.011,3.078)
The red and blue intersection ^
Blue and green: (12.283, 3.945)
Red and green: (2.405, 12.835)
Hmm I thought you might be able to shift the plane and cleverly apply picks theorem but the numbers don’t work
I gtg but it’s probably a tricky application of picks
Yea one of my classmates asked the prof and he said you can’t use it
Bruh
Ikr 😭😭
I never heard of that theroem but whatever ☹️
Is there some type of theorem to calculate lattice points or no?
One way is to see that he triangle is bounded, so you can draw a square around it and count the lattice points in there that are withing the triangle's bounds (think of it as inequalities)
Like. Points inside the triangle respect a certain set of inequalities.
Yeah well you don't need the square to be exactly around it.
The idea is that if you draw a square with vertices on lattice points, then say a square with side c will have exactly c^2 lattice points inside it.
Ohh
And since the square is finite you can check the lattice points yourself
So a square with all it vertices on lattice points and use picks theorem?
Idk what picks theorem is but I’ll figure out how to use it
I assume picks theorem is to find lattice points?
A square or a rectangle would work as well
Interesting
Picks theorem gives you the area of a polygon, but its vertices must be lattice points.
It won't help too much.
So how am I going to find lattice points?
What I mean is if there are c^2 lattice points in there, well c^2 won't be that big so you can check them
The sidelength of the square you draw
Ohh okay
But I suppose the square needs to be quite big here, so it might be too many points to check
Closed by @rocky moat
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 it increasing, stationary, decreasing and why
!status
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
If the derivative of a function is positive do you know what that means for the original function
not too sure
that means
the slope is positive?
of the tangent
i think
Yes
Yes
OK
so wait
the question is asking
what is the bevavior of the 1st derivative if the 2nd one is greater than zero
its increasing because its over 1 means it positive
correct?
ok i think thats right, thank you @final skiff
Idrk know what you mean by “its over 1”
But since the derivative is a function itself, then the second derivative is the derivative of the 1st derivative so we apply the same logic as before.
More mathematically we can let g(x)=f’(x). Then g’(x)=f’’(x).
Then use your answer to this
Yeah that is correct
Closed by @fresh copper
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 check my working so far, and help me with where to go next with this implicit differentiation problem
Image
@near meteor Has your question been resolved?
i dont think anythigns wrong here
Cool I’m just struggling a bit with algebra and what the next step would be
Trying to write it in terms of y’ on the left
Do you think you could tell me what to do next
@near meteor 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.
Could someone check my answers/help with the ones I haven’t done^^
Please don't occupy multiple help channels.
Oh I closed the other
@hard cave Has your question been resolved?
hello!
They have a rule about assisting with tests/exams. Not sure if that extends to quizzes, or I'd have attempted to assist.
Oh it’s not a test or an exam
It’s a test my knowledge/just a homework
I attempted the bottom ones
hii!
@hard cave Has your question been resolved?
Closed by @hard cave
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.
im not rly sure how to go w this
i changed it to like
$$2n!/3!(2n-3)! * 3!(n-3)!/n! = 11$$
✯✡ρєввℓєѕ✡✯
but then idk what to do next
@raw quest Has your question been resolved?
ttry simplfying the factorisals
im not sure how
you don't
you're focussing on the wrong component to simplify
Closed by @raw quest
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.
If I am trying to find the sine of angle theta
I have to do opposite over hypotenuse, correct?
However, my work source says the answer is 0.909
11.9/28.7= 0.414
not 0.909
Closed by @vestal rock
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 this area
imagine unrolling that rectangle
what are the side lengths corresponding to when you reroll it
2rh
idk then
use the circumference
Closed by @lethal bridge
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 happens to the graph of a trigonometric function if it has a positive phase shift?
positive phase shift indicates movement to the left, but does anything else happen?
what kind of thing do you want to happen
only change is moving to the left
nah just horizontal translation
horizontal translation,,, only to the left?
nothing specific, I just should know what will
depends on whether the phase shift is positive or negative
if i have a trig function like sin(x), then i consider sin(x + c)
when c > 0, this translates sin(x) to the left. when c < 0, this is a horizontal translation right
I see
and for positive change it will always move to the left?
for positive change?
as long as the number being added to the x is positive, yes it's a shift left
Closed by @vestal rock
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.
Help with all starting with d
i was thinking for d) 2sinx = cos 2x
Cos 2x is Cos ^2x - Sin ^2x ( i dont know how?
And Cos ^2 x is 1- sin^2 x
So we get 2 sin x = 1- 2sin ^2 x
@turbid heath Has your question been resolved?
cos2x=cos^2x-sin^2x
An identity
@turbid heath
$2sin^2x+2sinx-1=0$
L'empereur
Closed due to timeout
Use .reopen if this was a mistake.
That's a quadractic in sinx
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 correct
you can use symbolab to see if you've got the right answer
Whats symbolab
I dont trust ai
Ive already messed up too much cuz of trusting ai
its correct
Closed by @atomic sparrow
Use .reopen if this was a mistake.
But the highlighted 3 didnt got multuplied
wait
i was just tryna figure out
why it wasnt right LMAO
i didnt catch that
\
gimme ur new answer
my bad :(
I cant believe an Indian maths guy betrayed me
im not indian 💀
The video i was watching was Indian
I was tryna learn rationalisation
Why subtract them? Its =
Why it isnt the same 😭
Welp how do I learn rationalisation of such type of questions
u were doing it right
lemme just see why its not the same
hol on
hm u did do it right tho
i cant find any error
But i didn't multiply that highlighted 3
Why would the 3 be squared
you transcribed it wrong here
damn that was hard to catch
from 3√15 to 3√5
then its right
My point is how do I do 2 √3(2 √2 - 3 √3)
$2 √3(2 √2-3 √3)$
distribute it
2√3 * 2√2 = 4√6
2√3 * 3√3 = 2 * 3 * (√3)^2 = 2 * 3 * 3 = 18
so 4√6 - 18
.reopen
✅
Oh i got it
Can you give me a question of same kind and i try to solve it to see if i understand please? @spice frost
try simplifying (2√2-3√5)/(4√2-√7)
kk I'll mention you once am done
bet
two of those terms in the end r incorrect
@atomic sparrow 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.
Can you show the correct way completely as am not able to understand
Or can someone else do it with explaining each step
$(a+b)(a-b)=a^2-b^2$
∫oosh (lemonsaurus appreciator)
$a^2-b^2\neq(a-b)^2$
∫oosh (lemonsaurus appreciator)
I mean the whole question
This
@atomic sparrow Has your question been resolved?
faiyrose
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.
is more information needed?
no that should be good enough
Closed by @tall sun
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 does one find the integral without finding the function
.close
Closed by @fickle jungle
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 white is the question the gree is the solution
I dont really follow their steps
u = x^2 - 3
du = 2x
that appears to be the same thing to me, basically
Its the next bit
to get x I need to rearrange this to get sqrt(u+3)
Then subbing everything in I get sqrt(u+3) (u)^4 (2du)
Which is very messy and probably wrong
how did they get (1/2) (x^2-3)^4 (2x dx)
u-sub when you don't do weird things
Yes I know I did something wrong and they did it right... what was I supposed to do
no
x²-3 is your u so that will be u^4
Then you have dx, want du
du/dx = 2x
So dx = du / 2x
Hence it's integral of x u^4 du / 2x
= u^4/2
And if you had x terms left over, then convert them to u
Closed by @fickle shell
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'd like to know what was done in 2-(3-x) to get to this
Closed by @peak spire
Use .reopen if this was a mistake.
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 am completly stuck on how to go about solving this
the answer is 54/11 how would i solve this quuestion to get that answer
.close
Closed by @humble sage
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 this correct ?
yes, you can also double check them by plugging them back in for x on the LHS and seeing if you get 0
One more
yes
@winter osprey Has your question been resolved?
Closed by @winter osprey
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 do this without a calculator?
how do i solve this without a calculator?
do you know what csc is in general?
uh
cosecant
right but it's related to another trig function that you've hopefully practiced calculating before
oh
probably have not
i started trig about 2/3 days ago now
so you don't know how cosecant is defined?
i'm curious how it was introduced to you in the first place, then
barely is how
independent study leads to a lot of dumb questios
ok so
co·se·cant (ˌ)kō-ˈsē-ˌkant. -kənt. 1. : a trigonometric function that for an acute angle is the ratio between the hypotenuse of a right triangle of which the angle is considered part and the leg opposite the angle.
that seems right
sure
is there another trig function that involves the hypotenuse and this "opposite" side?
sine?
sorry, went for food
cosecant is the opposite right?
reciprocal
Now you have to know how to find sin(330)
@tall sun Has your question been resolved?
Closed by @tall sun
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.
im so confused on how the first circled step turned into the second circled step
im not so good at math but they transposed the 5/6r to the other side right?
how did it become 19/6 r??
they subtracted 5r/6 from both sides
np
@winged ivy Has your question been resolved?
Closed by @winged ivy
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.
Am I misunderstanding the idea of a null hypothesis? I'm doing a review assignment and I want to make sure I understand everything before I move on
so your answer is incorrect?
I want to know if it is before I submit it
I want to be sure
The assignment can't be resubmitted
if i'm wrong, i'd like an explanation of what i did wrong, please
So what does the claim "fewer than 16 in ten thousand male fireflies are unable to produce light" look like, using an inequality with p?
"fewer than 16 in ten thousand" looks like p<16/10000, which is p<0.0016
which is the null hypothesis
and p>=0.0016 is the alternative
hence why i answered the way i did
What led you to believe that this is the null hypothesis
Isn't the null hypothesis usually the initial claim being made?
So, the null hypothesis is the initial position stating no relationship/effect, that a study seeks to either reject or will fail to reject. In our case, the entomologist is claiming that fewer than 16 in ten thousand (or 0.16%) male fireflies are unable to produce light due to a genetic mutation. So, the entomologist is claiming that some relationship does in fact exist, and is testing this against the null hypothesis
What technical statement would be saying that there is no relationship at all? What you said means that the alternate hypothesis has to be p < 0.0016, but the null hypotheses are all completely equal statements or inequalities without inclusion
would it then be c, because that's the only one with alternate = p < 0.0016?
Null hypotheses don't exist until a hypothesis is made. As soon as a hypothesis is made, such as some proportion of fireflies not producing light due to a mutation, the null hypothesis comes into existence asserting the opposite of that
The opposite of that would be h0: p>=0.0016
but the issue is that there's no option that allows it
only p=0.0016, or changing the alternate hypothesis to be inclusive
So it would be C, and the reason why the null hypothesis isn't p >= 0.0016 but is p = 0.0016 is for a few reasons, mostly simplicity and to be conservative
alright, understood. can we go on?
It's left-tailed, and the critical value for a=0.05 is -1.645
Correct, right?
Actually, often the null hypothesis in a class is sometimes always said to have an equals sign. YMMV though
I see
is my reasoning here logical?
How did you arrive at that
The critical value when alpha is 0.05 is usually 1.645 in a standard normal calculation, and due to it being left-tailed, the answer is negative.
Looks fine, the answer should be right
Sorry I was just working on my hw and was actually trying to get help myself on a diff topic
also, no worries
thank you for helping in the first place
if you wanna leave and do your own work, that's fine
Yeah I got the same thing
I'm not sure if it would be A or D just because of the phrasing of it
alot of the questions are like that
I'm leaning a bit towards A since it follows a sort of double negative pattern in the same way that the question is asked, and D makes a stronger statement about what the null hypothesis is, when it's not explicitly stated
So the alternate hypothesis is "the cereal packets weigh >14oz on average", and the null hypothesis is the rejection of that claim
since h0 and h1 are mutually exclusive, wouldn't they be more or less the same?
the null hypothesis is that it's less than 14 oz
rejecting the null hypothesis would be rejecting that
So yes, but your professor (and others) seem to follow a format where the null hypothesis is that the mean weight is equal to 14oz (based on the answer from earlier being $H_0 : p = 0.0016$
Menelik
ah, fair
this is why stats confuses me, alotta room for interpretation
calc feels more peaceful
ordered chaos
instead of chaotic order
In this case, referring to the null hypothesis as "the rejection of the claim that the mean weight is at least 14oz" is always true, whereas referring to it as "the claim that the mean weight is less than 14oz" is a bit more roundabout, and can be interpreted as an alternate hypothesis itself
well, that's a headache and a half
And then, "reject the null hypothesis" is sort of a double negative, which the first option follows better since it says "there is not sufficient evidence to warrant rejection of the claim that ____"
i have to head off soon, pretty important test to take tomorrow
Yeah, especially since it uses words, and we kind of go into stats already having ideas of how to organize sentences and the meanings of specific words
Which you have to get used to
vs. calc is like "i've never seen $\int$ before so I believe it means whatever you tell me it means"
Menelik
Good luck w that, sorry if you had more questions you were trying to get through
You don't need to apologize, friend. you've done enough and i really appreciate you for it
thank you.
damn, no worries though.
You don't have to be!
It's confusing and a headache
That's all of stats
You still helped me understand things i wouldn't have otherwise
i appreciate the help, lad
thank you for the help, @trim hornet 💙
.close
Closed by @tropic hill
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.
can someone please help me understand this? i’m completely lost right now
please help teach me how to solve this
You want to find all $n$ such that $6n > 42$
Ari
@steady nymph 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.
Anyone how to do this qn.
Closed by @thorny heron
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.
can anyone help me learn how to graph in desmos? i've been trying to mess around with it for the past hour but have had 0 success.
Here's the answer
type the function out verbatim
do you mean like f(x) = -7882x + 7470 into the calc
Yep
https://files.catbox.moe/juqgi2.png
this is what i currently have and apparently (1,-412) isn't correct
or the others in the table
and i don't know how to proceed from here
feels like i keep going back and forth
(1, -412) is definitely a point on that line
Also the reason you can't really see the line is because the gradient is too large for the scale
Go to settings and extend the viewing range of the x axis
-12000 < x < 12000 for starters
done, just leave the y-axis alone or is there a way to figure out the right number?
Oh wait, other way round. Change the y-axis
The range of x-axis should be between 0.8 and 1
While the y-axis should have the large range: try -1200 < y < 1200
@tough cradle
@tough cradle Has your question been resolved?
Interval? Don't you mean x-intercept?
my question is asking for the intervals
and i really have no idea how to get this as i've never done something like this before
i've been re-reading the book and watching the example but i feel stumped
for reference, this is the only example i'm given
@tough cradle Has your question been resolved?
@tough cradle Has your question been resolved?
@tough cradle Has your question been resolved?
the intervals would presumably be the viewing range
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 sure how to start, my only thought is finding the stationary points or something but not sure
yea u should start by finding the stationary points
what do you think you can do next?
i cri
help
ok so to ensure that the cubic equation has three distinct real roots its derivative should have two distinct real roots that basically means that the functions changing its direction twice
what are the critical points?
water beam
$\ x\left(3x+2a\right)=0$
water beam
$x=0,\ -\frac{2a}{3}$
water beam
these
right
so now
for the cubic polynomial to have three distinct real roots the function should change direction at both critical points meaning one should be a local maximum and the other a local minimum so you should evaluate the second derivative at the critical points
let me know whatever you evaluate
$y"=6x+2a$
water beam
$y"\left(0\right)=2a$
water beam
$y"\left(-\frac{2a}{3}\right)=-2a$
water beam
done
i dont know what A is so i cant really tell
okay
but it cannot be zero as that would eliminate the quadratic term and reduce the cubic equation to a form that doesn’t provide the necessary three distinct roots
yes
yea so if a>0
y''(0)=2a>0 (local minimum)
y''(-2a/3)=-2a<0 (local maximum)
and if a<0
y''(0)=2a<0 (local maximum)
y''(-2a/3)=-2a>0 (local minimum)
so you can clearly see a>0 and a<0 both works
yes
so that's it
is there like a slot where you can write whatever you want to?
💀
lol
i mean my theory isnt wrong either
💀
bruh how can they say that
we're literally getting 2a and -2a
how tf are they not inflection points
😭
do you wanna watch something funny
yajat
u failed me
ur supposed to be number 1
jee adv
😭
REACT TO THAT FUNNY VIDEO
stfu
NAH BRUH tell me what part of my explanation sounds wrong
bro it dont matter if ur explanation is wrong or right what matters is that u didnt find the value of A or get the question right
😭
@lethal bridge 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.
No matter what i do i reach a dead end
substitute cot and then IBP
Won’t you need the exponential integral for this
has that been taught to you?
You mean integrating e to the power of anything? Im not really that good at that
kheerii
You’re right in saying that the function is non-integrable
Without the use of non-elementary functions
This is an example of one
I should be able to solve it with u-substitution, atleast this is what the professor says
Idk if he also included IBP tho
I’d not be surprised
See, the answer has a non-elementary function in it
Maybe they meant $\int e^{-\cot x}\csc^2(x)\dd{x}$
kheerii
Try doing this
Yeah here i can do -cot x = u where dx = du/-csc^2
Then make it integral of e^u -du, and the result would be -e^u
It should just be e^u?
Remember that $\frac{d}{\dd{x}}(\cot x)=-\csc^2(x)$, not $\csc^2(x)$
kheerii
Yes
Closed by @hollow snow
Use .reopen if this was a mistake.
how to find the value of inverse trignometric function value if the input is negative, doesnt include in principle value
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 many integer solutions does the equation $x_1+x_2+...+x_7 = 24$ have that satisfy $x1+...+x4 = 10$ , $x_5+x_6+x_7=14$ and $x_i \ge 0 for i = 1,2...,7$ ?
Merineth
my solution was $\binom{30}{24} - \binom{13}{10} - \binom{16}{14}$
Merineth
But the book says it's $\binom{13}{10}\binom{16}{14}$
Merineth
Why is that the case?
My assumption was that i take the total sum of possible solutions and then remove the possible solutions for the conditions?
if you have this
then you have this
so you can choose (x1,...,x4) independently from (x5,...,x7)
so how many ways to have x_1+x_2+x_3+x_4 = 10 and all >=0?
it's 13C10
how many ways to have x_5 + x_6 + x_7 = 14 and all >= 0?
16C14
These 2 conditions
make this condition useless
seems odd to include that condition if it isn't used?
well that's the point, it's your job to find out which conditions are useless
though let's say this condition wasn't included for example
well you can still find back the same number of ways
by saying:
x_1 + x_2 + x_3 + x_4 = 10
x_1 + .... + x_7 = 24
so x_5 + x_6 + x_7 = 24 - 10 = 14
Why doesn't my solution work tho?
well I don't understand how you even got that
If i take the total amount of solutions from the equation $x_1 + ... + x_7 =24$
Merineth
Right? That would be 30C24
sure
and then i want to reduce tthat total with my two conditions
but then you have to get rid of the solutions to ... = 24 such that ... is NOT 10 and ... is NOT 14
I don't know how you would adjust that
$x_1+x_2+x_3+x_4 = 10$ Well we know that this conditon has to be met?
Merineth
Merineth
I get that the sum of these two are the total combinations for my two conditions
I don't see how multiplying these two together results in the answer i want?
why do we multiply and not add?
you don't ADD here
ADDING is for this situation:
"You have 5 ways to get an A+ if you didn't go to class.
OTHERWISE, you have 11 ways to get an A+ if you DID go to class.
In total, you have 11+5 = 16 ways to get an A+"
Multiplying is for this situation :
"You have a 2-digit passcode.
You have 10 choices for the first number.
AND, you have 10 choices for the second number.
In total, you have 10*10 = 100 choices for your passcode"
I've been following along with rafilou's explanaton and how I've understood is:
For every solution to x_1 + x_2 + ... x_4 = 10, you can pair with each solution to x_5 + x_6 + x_7 = 14 to sum up to 24
- Adding is for INCOMPATIBLE CHOICES, "A or B". (meaning both can't happen at the same time)
- Multiplying is for INDEPENDENT CHOICES, "A and B". (meaning one doesn't affect the other)
Hmm i guess i'll just have to accept that it's multiplying
@ebon depot try to understand what is being done in those 2 scenarios
and understand what is the difference, meaning why we should add/multiply instead of doing the other
Yeah i see what you mean by the passcode example but i can't seem to apply it to my problem
But it is what it is
I got it nearly correct
well, what you choose for your first digit doesn't affect what you choose for your second digit
here, no matter what you choose for x1,x2,x3,x4
it won't change the fact that x_5,x_6 and x_7 need to be picked such that x_5+x_6+x_7 = 14
so what you choose for x1,x2,x3,x4 doesn't affect what you choose for x5,x6,x7
since you have 13C10 ways to choose x1,...,x4
and 16C14 ways to choose x5...x7
you have 13C10*16C14 ways to choose x1,....,x7
\o/ i dont know what to say haha i sincerely dont get it but it's alright, i'll just try and remember when i want the total amount of combinations such as the passcode i'll just multiply them together
thanks for helping tho 🫶
.close
Closed by @ebon depot
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 this correct? I tried different apps and they all say it’s 1 except one said it doesn’t exist. It looks like it’s not approaching anything from the left side so that means the limit doesn’t exist, right?.
I would quibble about the final ln(L) = 0 = e^0 = 1, but surely you meant ln(L) = 0 => L = e^0 = 1.
I don't see a mistake. We are approaching pi/2 from the left side. So the fact that is only defined on the left side is fine
@wind kettle Has your question been resolved?
Closed by @wind kettle
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.
a canon is at an angle 45 deg to the x,y- axis. A canon ball is fired at a velocity of 600 m/s. A man is standing 300 km away from the canon. at what height will he see the ball above him? Also, a man is standing 60 km away from the man and canon. The weight of the ball is 5000 kg. The weight of the man is 143 kg. There is a nail 1 km away from man_2. Find how inside the nail will pierce his skin. Consider the deceleration of the nail with the man to be 5000 m/s.
the breadth of man_2 is 20 cm. If the nail passes half of his body, he shouts. Tell how many times he will shout, i.e., how many times he passes half the breadth of his body.o
if g = 1 m/s**2
@potent reef 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.
If 𝒇(𝒛) = 𝒖 + 𝒊𝒗 is an analytic function ,find 𝒇(𝒛) in terms of 𝒛 𝒊𝒇 𝒖 − 𝒗 =𝒆 𝒚−𝒄𝒐𝒔𝒙+𝒔𝒊𝒏𝒙 𝒄𝒐𝒔𝒉𝒚−𝒄𝒐𝒔𝒙 𝒘𝒉𝒆𝒏 𝒇(𝝅𝟐) =𝟑−𝒊𝟐
@still temple Has your question been resolved?
.close
Closed by @sharp bolt
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 help with this calculus problem.
x= (v^2sin(2θ))/32 where 45 ≤ θ ≤ 135
and I need to find the equation for dx/dt
it also says that dθ/dt is constant, which I think is important
this is the actual problem I'm looking at
I think I only have one more chance to try answering it before the question locks up and gets stuck as incorrect
note v is a constant
something about my chain rule has to be off, yeah
if v is a constant, then should the derivative function remove it completely?
or just not derive it?
like pull it out front along with 1/32 before deriving what's actually left
Does this look right?
yes but theta being a function of t is messing with my gut checking
So t is the independent variable, v is the velocity at which water is moving away from (0,0), theta is the angle it's going in, and x is how far from (0,0) the water lands
While v is constant, the water is moving away from (0,0) at a constant speed. The rate that theta changes at is constant, and then the ultimate dependant variable then is x, how far away the water lands, or dx/dt, at what rate that landing point is changing relative to the center (0,0)
@iron onyx Has your question been resolved?
.close
Closed by @iron onyx
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 first picture is a definition of Lebesgue integral written in RCA by rudin, and the second picture is a definition of Bochner integral written in Integrals with values in Banach spaces and locally convex spaces by Piotr Mikusinski. (https://arxiv.org/pdf/1403.5209)
Since the Bochner integral is Lebesgue integral defined on Banach spaces, I thought that these two integrations should be constructed in almost the same way.
But as we can see from the picture, the Lebesgue integral is constructed using supremum, while the Bochner integral is not.
Is it just difference of notation and are they using actually the same method? Or is there a reason that Bochner integration cannot be constructed using supremum, just like Lebesgue integral in RCA?
I want to rewrite a definition of Bochner integral like (2.1) in the first picture.
@modest trellis Has your question been resolved?
<@&286206848099549185>
i uploaded the same question yesterday, but it closed while i was sleeping 😦
@modest trellis Has your question been resolved?
<@&286206848099549185>
Closed by @modest trellis
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.
Can anyone help me solve this? I really don't know how to do this and I'm struggling
related rates problem?
you most likely want to find an expression for the area of the rectangle and then use calculus to find the maximum value of that area
the unit is called optimization problems
I think what I'm supposed to do is make the derivative formula for the rectangle and then find where it equals 0 and... do something with that. I don't know how to use the formula for the circle to help me either. It has to be there for a reason
that sounds good
remember that when you take the derivative it gives the instantaneous gradient
so at f'(x) = 0 your gradient equals 0
which will be either a minimum, maximum or stationary point of inflection (you can find which using the second derivative)
This is all I have so far
so your thinking process should be
- How can I find the area of the rectangle given an expression for y = some function of x
- How can I maximise this? As our area will form a graph we can take the derivative, find stationary points and then your maximum point
- At maximum point substitute in to find the maximum area
At least that's my thought process
I think you might have the area expression wrong
since it's the area of a rectangle we will most likely use the form width*height of rectangle
it should be 2xy, shouldn't it?
and both sides should be the same as the shape is symmetrical
I'm looking at this and your width of rectangle seems to be 2x
when going to the point x,y you can see at x = 4 width is [-4,4] = a length of 8 so the length will be 2x
your height would be y as given on your circle but as you can see y on the circle is equal to sqrt(25-x^2)
this should give you an expression with just x
A=2x*sqrt(25-x^2)
oh my god
you're right, the x substitute for y is already given at the start
I was just wracking my brain over how I was gonna find it and how that circle formula was supposed to help me
the key thing about optimisation problems is that you know the height and width are dependent upon each other
so you just need to think how each part of your area will change and how to calculate them 👍
right, and the thing that was confusing me about that earlier when I tried to derive the area was because I felt like deriving x shouldn't just give me a dx/dx. Like I feel. like there should be a rate of change for x to correlate to dy/dx
but I think this fixes that whole problem
I think
you should be able to take the derivative of this using product and chain rule!
right, so that'll be, 2dx*sqrt(25+x^2) + x/sqrt(25-x^2), right?
no wait, gotta add in the derivative of what's inside the square root too
2dx*sqrt(25+x^2) + 2x^2dx/sqrt(25-x^2)
I assume you mean 25-x^2 for the first?
also I don't think you should have dx left over because d/dx(2x) = 2
and I think it should be 2/srt(25-x^2) for your second term? Let me check
Right, ok, so d/dx of x should still cancel itself out here
here is the answer if you are curious
I would encourage you to go through the working out ofc
note that the first part of the product rule was multiplied by sqrt(25-x^2)/sqrt(25-x^2)
I see
Yeah I definitely want to show my work, I need to understand what I'm doing
I think I've seen that sort of thing before, multiplying the top and bottom by the square root to get it into the denominator. I don't understand why you would do that though
it's just a simplification thing
the reason for it in this case is to fit to the denominator of the second part of the product rule which is already sqrt(25-x^2)
since it's in one fraction it is simplified further in this case
also conveniently this also removes the square root of the left expression which gives you a non-root for the denominator
I see
I'm gonna need to do more work I think to fully understand this
For now though, idk. I should actually go tend to dog. She's getting restless
@iron onyx Has your question been resolved?
Closed by @iron onyx
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.
|sinx|=sinx+2cosx find solutions between [0,2π]
you can get rid of the abs vals by considering separately the cases where sinx >= 0 and sinx < 0
Could just directly say that tanx=1
π/4
messed up signs
5π/4
But is this a valid solution?
Wait, you messed up here
2sinx-2cosx=0
how are you getting that
$-\sin x=\sin x+2\cos x$
kheerii