#help-39
1 messages · Page 101 of 1
12x + 8 is the derivative of f(x)
at any x
the x u need to find the derivative at
is -3
so just plug it in
that is literally the same thing
yeah
that’s was i was confused at
that means the slope of the line tangent is the same thing as iroc?
is this right for c?
,rotate
at x=-3 , plug that in ur f(x) to find y coordinates , and then use that
and not use use anything for y?
Closed by @midnight coral
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 m_i and 1/m_i , m_i>0 i=1,2,3,4 are four distinct points on a circle then prove that m_1 ×m_2×m_3×m_4=1
Opposite angles in a cyclic quadrilateral add up to 180 might help
@dark ingot 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 do I solve for the** minimum value of F** to get a quadratic with roots that are complex conjugates
@delicate dock Has your question been resolved?
@delicate dock 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.
@teal hazel 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 would i attempt to do part b. I can't seem to get to the answer
its a mechanics question
@wheat vale Has your question been resolved?
<@&286206848099549185>
thank you 🙂
i got 40 seconds but as the time for deceleration of N
i didnt know what to do after that
yh
the mark scheme graph looks like this
?
sorry i didnt understand the seperating the speeds
yh
yh that makes sense
wait so how did u construct the N equation? cause i saw that on the ms but didnt know how to get to that
is it the area?
hmm im sorry but i still dont think i understand this 😦
yh split it into triangle and rectangle or area of the trapzium it will equal the displacement 975m
yes
idk
im stuck on that do i use M or N
yh but idk how i got to 40
like i used s=ut+1/2at squared
and then made u = -30/t
sorry i meant a
u know what dw
its fine
ill try to get through the ms
its fine ds
dw
ok thanks for the help
@wheat vale 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.
why isnt the result 0? i dont understand, on the denom theres x and on the top theres x-x so why not 0
denom is inf * 0 so already non trivial
i would analyze the limit of the denominator first separately
yes
the x is a stronger inf and wins
so the denom is x
how
can u explain bro
l'hopital
@drowsy flare Has your question been resolved?
@drowsy flare Has your question been resolved?
Cant do without?
idk?
can u show how u found with hopital
i didnt do it
define F(x) = (sqrt(x^2 - 2) - x) / (x arctan(1/x^2)) = (sqrt(1 - 2/x^2) - 1) / arctan(1/x^2)
now let f1(x) = sqrt(1 - 2x) - 1, f2(x) = arctan(x), g(x) = 1/x^2
we find that f1'(x) = -1/sqrt(1 - 2x) and f2'(x) = 1/(1 + x^2)
then F(x) = f1(g(x))/f2(g(x))
using l'hopitals lim x -> inf F(x) = lim x -> inf [f1(g(x))]' / [f2(g(x))]'
= lim x -> inf f1'(g(x)) g'(x) / [f2'(g(x)) g'(x)]
= lim x -> inf f1'(g(x)) / f2'(g(x))
= lim x -> inf [-1/sqrt(1 - 2/x^2)] / [1/(1 + 1/x^2)]
= -1/1 = -1
shouldnt f1 be sqrt(1-2/x^2)-1?
you could define it that way and then define f2 as arctan(1/x^2)
but the way i defined it always you to skip a bit of computation, admittedly not much
as you get the g'(x) to cancel (from chain rule)
nws
\begin{align*}
F\left(x\right) &= \frac{\sqrt{x^2 - 2} - x}{x \cdot \mathrm{arctan}\left(\frac{1}{x^2}\right)} \
&= \frac{\frac{1}{x} \left[\sqrt{x^2 - 2} - x\right]}{\mathrm{arctan}\left(\frac{1}{x^2}\right)} \
&= \frac{\sqrt{\frac{1}{x^2} \left(x^2 - 2\right)} - 1}{\mathrm{arctan}\left(\frac{1}{x^2}\right)} \
&= \frac{\sqrt{1 - \frac{2}{x^2}} - 1}{\mathrm{arctan}\left(\frac{1}{x^2}\right)} \
\text{Define } f_1\left(x\right) = \sqrt{1 - 2x}& - 1,, f_2\left(x\right) = \mathrm{arctan}\left({x}\right),, g\left(x\right) = \frac{1}{x^2} \
\text{then } f_1'\left(x\right) = \frac{-1}{\sqrt{1-2x}} &\text{ and } f_2'\left(x\right) = \frac{1}{1 + x^2} \
\text{and } F\left(x\right) &= \frac{f_1\left(g\left(x\right)\right)}{f_2\left(g\left(x\right)\right)} \
\
\text{Note } \lim \limits_{x \to \infty} f_1\left(g\left(x\right)\right) = 0 &\text{ and } \lim \limits_{x \to \infty} f_2\left(g\left(x\right)\right) = 0 \
\text{hence (by L'Hopital) } \lim \limits_{x \to \infty} F\left(x\right) &= \lim \limits_{x \to \inf} \frac{\left[f_1\left(g\left(x\right)\right)\right]'}{\left[f_2\left(g\left(x\right)\right)\right]'} \
&= \lim \limits_{x \to \infty} \frac{f_1'\left(g\left(x\right)\right)g'\left(x\right)}{f_2'\left(g\left(x\right)\right)g'\left(x\right)} \
&= \lim \limits_{x \to \infty} \frac{f_1'\left(g\left(x\right)\right)}{f_2'\left(g\left(x\right)\right)} \
&= \lim \limits_{x \to \infty} \frac{\frac{-1}{\sqrt{1 - \frac{2}{x^2}}}}{\frac{1}{1 + \frac{1}{x^2}}} \
&= \frac{\frac{-1}{\sqrt{1 - 0}}}{\frac{1}{1 + 0}} = -1
\end{align*}
@drowsy flare
Where did x² go in first step?
hows this
Acman
Thx
.close
Closed by @drowsy flare
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 the circled parts as i did 3/1500 does not equal 15/1500 * 45/1500
@hollow pike Has your question been resolved?
@hollow pike 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 someone tell me the formula
Uhhh... can you be more pacific?
Let Ω denote the area in the first quadrant between the line y =
16 and the curve y = x^4. When the curve Ω is rotated one revolution around y-
the axis forms a body of rotation. Calculate the volume of the body.
like this
for x=axis its $2\pi \int ^a _b \sqrt{1-\frac{df}{dx}}dx$
be more atlantic
Right, you need the integral
whats that ?
$2\pi \int ^b _a xf(x)dx$
"Let Ω denote the area" and then "When the curve Ω"
What is it, an area or a curve
i was just poking fun at aki's message haha dw about it
my professor have done like this
volume of a rotated body
but i wanna know the formula and the difference between when its a volume and the rotation area both on x and y
Yeah but the questions defines Ω as an area and then refers to it as a curve
spookyspaghetti
that for around x-axis
and for y?
for y-axis its $V = \pi \int _{f(a)} ^{f(b)} (f^{-1}(x))^2 dx$
spookyspaghetti
with $f^{-1}(x)$ the inverse function of $f(x)$
spookyspaghetti
so why have my proffesor have 2pi?
here
not a clue
this is the rule he uses
okay nw i will just use it xD without understanding why
thats why i am confused
the rule when i search it up its only pi and not 2 pi
if i can see the function they use maybe i can see
yeah no idea
the one with just pi is the one i learned and it works fine
wikipedia says the same as me so idk
okay nw
i gonna ask it again here
maybe someone else
know this weird rule
.close
Closed by @errant flax
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.
nnmnmbn
mmmnmmnmnmnmbbbnnnbb
what have you tried?
sure
If we subtract 1/3 from both sides
okay
,w factor x^2 -x-5
Ayo don't cheat
is this even solvable analytically?
yes, its homework by teacher
ah ok then
So the important thing here is that you figured out this quadratic has 2 real roots
keep that in mind
okay
?
When you factor the quadratic
I didn't bother writing in the numbers
they're x_1 and x_2
yeah you have that - 1/3
So when will this be 0?
When 3ex….. is 1
ye
Aaaaannnnddd I'm honestly not sure what to do next
I thought it'd work out into a nicer form
what I would do is prob try sketching the graph by finding the roots (which you've done) and the turning point and then determine the shape of the graph
then see how many times y=1/3 intersects the graph
Oooohhh
inflection points?
do you know how to find turning points?
this is about extremes again
first derivative test
yh
i think
Remember Rolle's theorem
it comes in handy here
Do the same analysis we did before
find the extremes
,w differentiate (e^x)(x^2-x-5)
,w solve (e^x)(x^2 + x -6) = 0
Nmm
we got two critican points, one maxima one minima
critical point 2 evaluated makes a maxima
you don't have to do that here
what do they mean, the numbers
I mean yeah, you could figure it out from these numbers but like, it's not certain in general
think about the two numbers 7/e^3 and -3e^2. Is there really a need to do second derivative in this case
You can have situations like these for example
I know what you're getting at
but it's bad practice
in my book
it's good practise though imo to logically think and never always rely on doing more maths. Like isn't it better to think actually think about it than always do maths routinely. The function here is cts so that situation is mitigated
It's not when you're new to something because all of that can confuse you. It's best for op to learn the methodology first and then figure out tricks later
,w differentiate (e^x)(x^2 + x -6)
Anyway, we got our extremes
Just plug in the x values and check the signs
Nn
minima
Good
now wat
Best to check limits
ohh
horizontal asymptotes
yeah
wolfram is drunk
,w lim x to +infinity (e^x)(x^2+3x-5)
it's inf
Ahhh
inf times inf is inf
okay
now check for -inf
0
,w lim x to -infinity (e^x)(x^2+3x-5)
how 😭
Don't mind my inaccurate graphing
Omg my pc had a seizure
Well we knot the max and mins right
and we know that it goes to 0 on the left
to inf on the right
and we also know there are not extremes between -3 and 2 right
so we can also add
This
Right?
?
oh yeah because only teo critical points
two
yes
so the function must always decrease from x=-3 to x=2
at least in this case of a differentiable and continuous function
because if at any point it started increasing
it would have an additional minimum
we know it doesn't
so it can't
Remember Rolle
Can you do the visual justification
lowkey i studied rolles but forgot!
what does it say?
See how purple
in order to go up
had to have a bottom point
we know that it doesn't have those
anywhere else
so it can't do any ups or downs anywhere else
based on our analysis the function goes from -inf to -3 increasingly, then it goes from -3 to 2 decreasingly and then it goes from 2 to inf increasingly
which is what I sketched in blue
It can't make any other changes in up or down anywhere because it doesn't have extremes to do so
Basically
what is the number of solutions, 2?
Now that's the cool part
On our sketch we will now draw the line of y = 1/3
now let's first check
is 1/3 greater or lesser than 7/e^3
lesser
good
so I'll sketch it as suc
such
Now do you see how many solutions there are?
3, why?
yes
Look at what the problem is asking for
The number of solutions for f(x) = 1/3
will be the number of times the graph of f(x) crosses the line y=1/3
yes
so here's a bit more justification
in order to go from 0 at -inf to 7/e^3 at -3 the function must pass the point 1/3 once and exactly once
it can't pass it more than once since it has no extremes inbetween
and it can't pass it less than once since it can't do jumps
(at least this one can't)
due to continuity differentiability?
then going from 7/e^3 at -3 to -3e^2 at 2 the function must cross 1/3 again for the same reasons
and only once at that
ye basically
and then again to go from -3e^2 at 2 to inf at inf it must pass 1/3 once and only once again
so in total it must pass 1/3 three and exactly three times
meaning the equation f(x) = 1/3 must have 3 and exactly 3 solutions
So to summarize, we checked the extreme points to get the places where the function "turns" so to speak, then we checked how it behaves left and right of the extremes to see to which value it goes and then we sketched the graph and the line y = 1/3 making sure to position it accurately under 7/e^3
this gave us the answer
Lowkey hard
The reason we had to check the left and right limits
is because the function could've behaved like this
for example
and then it wouldn't cross 1/3
left and right
in light blue
had the right limit been 0
then it wouldn't cross 1/3 on the interval of 2 to inf
which is why we needed to check those
in order to accurately draw our sketch
By using a graphing calculator
lol
If you did everything right
the way I told you, then you must be correct
,w plot (e^x)(x^2 -x-5)
Imma give you another problem to practice this if you want
sure
yeah
đ
Here's your practice problem
see how many solutions that upper function has
for each of these y values
individually
Np, good luck
Closed by @stoic 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.
I’m having trouble showing the formulas highlighted in blue are equal, I expanded but then I get 2x*mu which I don’t know what to do with
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
That is the original
hiiiiii @merry carbon
The question says to prove this identity starting with the LHS and expanding the brackets
Try $f(x)=\mu=1$ and see that it is false.
SWR
I'm guessing the mu is supposed to be the integral of x [w/ limits] divided by (b - a) or something?
Or wait, what is mu supposed to be? Looks statsy to me 
It’s cut off a bit but this is the question
Define mu
Given your context so far, it's false
proceeds to mooo like a cow
Expected value mean
Oh this is some statistics shenanigans
yes
no, that's too evil for me
grrrrr
People often miss this bit
LMAOOOOOOOO
idk I thought mew mu was a giveaway it was stats 
FMTB
WHAT IS THIIIIIIIISSSSSS????
mind read me
it’s FMTB
I always assume it's not stats because stats are evil and I see no evil
what are we talking about it this lovely channel
stats
evil
maybe it's some ibp stuff
statistically some of most staticians have a chance to agree with that
Something either happens or it doesn't. If you ask me, it's all 50/50
[the $\mu$ is then basically $\int_a^b x f(x) \dd x$ then, right?]
@merry carbon
Yes my favourite statistician @last summit would definitely agree
(allow me, I don't know stats stuff
)
I think so at least that’s how E(x) is defined
And f is such that its integral between a and b is 1, yea?
I would never thought that you would swear
Stats will make anyone swear even the purest of hearts
Stats bring out the evil in me
Volume, charge, moment of inertia, electric/magnetic fields, current, ...
ye I think so

That's different, those are well established, liked and funny
In which case then, expand the brackets at the bottom and use that 
i don’t like those
Moment of inertia never hurt my expectations
too much love i will die
too little love i will die
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
Expand like get more integrals?
that’s me
Basically yea, split them up 
mu is a constant, you can take it out, and don't forget the f 
(does that at least help a bit @wild fable?
)
I think so 
Oh also turns out I should've known this 
How's it going? 
Not your fault, at all, blame stats
"pRoBaBiLitY DeNsItY FuNcTiON"
-wait is today becoming stats day for me 
Oh no, the end is coming 🕊️
@wild fable 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.
broda are you doing jee questions
i thought I had seen the last one before
so I'm going though the paper now
Ah
this is the 2024 paper
mmm
so Q would match to 3, right?
the differential at 0 would be 0
,w is x|x|sin(1/x) differentiable at 0
f(h) - f(0)/h , h tends to 0
so we have f(h)/h, h tends to 0
Closed by @sharp smelt
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 failing my final someone PLEASE help
Can anyone explain why theta is in between pi/2 and -pi/2 for the boundary circle???
(This is double integrals with polar equations)
think of arrows pointing from the origin to the rim of the shape
it goes between up (pi/2) to down (-pi/2)
@high geyser Has your question been resolved?
.close
Closed by @high geyser
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 if my answers to these 2 questions are right? we got them for homework but the solutions wont be discussed in class
jee ?
the food?
entrance exam
for next time you can check wih wolfram alpha and symbolab
yeah
i don't know where else do they give such horrendous questions
i tried but i couldn't get an answer 😭
im in highschool lol
lmao why not just plug in the value for sin(π/2)
yeah yeah we have calc bc in america
for high schoolers
also symbolab spit me an answer
I can say ur final answer is right for the first q
oh wait 😭 i thought we were supposed to do that after simplifying the derivative
okok ty
because it's (π/2)x ?
ohh where are the paranthesis
but 2nd question looks good
lemme redo one
yeah yeah I didn't see the paranthesis tho
yeah my bad
yup
I thought it would be a lot harder ngl
but maybe the harder questions are scattered
with some easier ones
it's not an exam question, this is for practice
yeah I just think the JEE and the other testing systems are kinda stupid
but I guess when you have that population
what to do
anyway good luck @wraith hawk
and have a good morning!
good morning
thank u sm
<3
heres the adv paper if u wanna see the questions in the exam btw
it seems p chill until I got to the physics part 😭
Closed by @wraith hawk
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 just if water is 1g/cm^3
the rectangles volume is 1 x 2 x 2 = 4cm^3
and the mass is 3
so mass/volume = density ( 3/4 = 0.75)
so it floats?
yes
@mild grotto 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 someone help me on how to find the domain and range for this graph as well as graphing it by hand
So
what are your two vertical asymtpotes
@wicked sluice
and what is your horiz asymptote
Domain
not sure tbh
Asymptote
is it just 0
could u quickly explain why that is pls
Range
why tho
this mean except 0 and from 0 to inf
I’m like 99 percent sure
exract the bottom
these r the solutions
im not too sure how there is like a second graph below the x axis
smallest value of the equation is -3.125 at x= -1/4
fr?
so that quadratic at the bottom
wdym by that
is that the (x-1)(2x+3)
like
yess
.
ohh how come its flipped
ig im not wrong with those range and domain tho
ur right for range
but for domain it’s just x cannot equal -3/2 and 1
it can still equal 0
There is a y intercept
on this graph
and ur domain implies there isn’t
what flipped tho
nvm
@wicked sluice Has your question been resolved?
Closed by @wicked sluice
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, is this even correct
If its 12sinx -5cosx=13 find sinx and cosx
There is an error in ur expansion of (13+5b)²
How
it is 169+130b+25(b)^2
after that use the quadradtic eq to slove for cos x
Okay
its (13b+5)^2 this time
srry my bad
ur right i didnt see properly
now u can plug it the eq 12a-5b=13 to get a
@lone nebula 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.
For a) this is what I did
I found the prob of finding no defective bulb which was
(2 (48 (50
0) 5) / 5)
And then subtracted that by 1
so 1 - 0.8081 = 0.19...
but for part b
Im not sure how to do it
$\frac{\binom 20 \binom{48}{5}}{\binom{50}{5}}$
Steakanator
that?
yuhh tysm
i dint know how to latex that
I subtracted that by 1 to find the prob of finding atleast one defectrive bulb
thats correct right?
seems fine
start by generalizing part a to any number of bulbs chosen, not specifically 5
how would I do that
do I just sub in a variable for 5 ?
which can be anything?
lol im not sure
go through the same thought process that got you to your first answer
if the inspector chooses n light bulbs at random without replacement, what is the probability he finds at least one defect?
$1 - \frac{\binom 20 \binom{48}{n}}{\binom{50}{n}}$
Calc III Victim
this?
so I just keep trying random values?
ohhhh
$1 - \frac{\frac{2!}{1(2)!} \cdot \frac{48!}{n!(48-n)!}}{\frac{50!}{n!(50-n)!}} > \frac{1}{2}$
and then solve for n?
i take issue with this term
Calc III Victim
better
alr gimme a fe wmins imma try solving and then get back to u

$- \frac{48!}{n!(48-n)!} \cdot \frac{n!(50-n)!}{50!} > -\frac{1}{2}$
Calc III Victim
one sec imma latex the whole thing bcz my handwriting is shittttt
$= - \frac{48!(50-n)!}{50!(48-n)!} > -\frac{1}{2}$
Calc III Victim
$=-\frac{(50-n)(49-n)}{50 \cdot 49} > -\frac{1}{2}$
Calc III Victim
$= -\frac{2450 - 99n + n^2}{2450} > -\frac{1}{2}$
Calc III Victim
$=\frac{-2450 + 99n - n^2}{2450} > -frac{1}{2}$
Calc III Victim
$= -1 + \frac{n(99 - n)}{2450} > -\frac{1}{2}$
Calc III Victim
$\frac{n(99 - n)}{2450} > \frac{1}{2}$
Calc III Victim
$n(99 - n) > \frac{2450}{2}$
Calc III Victim
Well if you keep the algebra going you end up with $$-n^2 + 99n - 1225 >0$$
Steakanator
So it's more or less just finding the roots
Closed by @vernal grove
Use .reopen if this was a mistake.
✅
But then I will get 2 diff values
how will I know which one is the solution
only positive
Im getting 14.496 and 84.503
oh
hm. no clue 

oh wait
im actually an idiot
ofc it cant be 84
we have 50 bulbs to choose from
smhhh 🤦
one more issue for part a in my book this is what the solution says
this wont be the same as mine right
It is the same
oh how
Your solution just includes an extra $\binom 20$
oh wait
Steakanator
Closed by @vernal grove
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’m trying to calculate Var(x) for f(x) but I don’t know what went wrong cuz it doesn’t give me the right answer
Isn't Var(X) = E(X²) - E(X)²
water beam
whats E(X^2) how do i find that?
Oh it's actually this lmao
yeah
dont i have to calculate the Var(X) for each of the parts in the piecewise separately and add them up thats why theres to mews sqwuared
,,Var(X) = \left ( \int_0^2 \frac{x^2}{8} \dd x + \int_2^5 \frac{x^2}{4} \dd x \right ) - \mu^2
𝔸dωn𝓲²s
I dont even think thats really true
It should be R instead of a to b
I would stick with this then
𝔸dωn𝓲²s
whats the difference with fsubX of x? and just f(x)?
Notice for R\[0,2]U[2,5] the integral is 0
just a notation to denote that this is density from random variable $X$
print("NAME")
o
ok
btw this was just a precursor to the actual question i wanted to ask 💀 i just had to complete this before asking the other one
wait
shit
ok...
at least you prepare for your exam with that one extra question
Closed by @wild fable
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 do i do?
!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
1
1
k
and what is C1 ?
combination 1
and how did u think of this equation, just trying to understand your thought procces
I thought you get one mark from each
you recieve an integer mark from 1-100 folr each category
so all the natural numbers in the interval [1,100]
I dont understand
mhmm let me see
to score a total mark of 200, the marks for design, technique, and originality must add up to 200, with each category scoring between between 0 and 100.
yh
lets use a generating functions approach to solve this problem. we can set up the generating function for each other category as follows
what is a generating function??
a generating function is a formal power series used to encode a sequence of numbers.
yes
How do u do it?
wait i will tell you
don't thank me chatGPT gave me the idea 😂
nice solution regard less
The power of ai ❤️
Thanks aswell Zaakoo
.close
Closed by @teal hazel
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 explain what part I did wrong ?
looks correct to me
i put it into the answer book like this and it said it was incorrect
ill send ss
the above was incorrect when i did the "check" so im not sure what part i missed...
maybe the ± needs to be next to 2sqrt(2)
ohh ur right
that was a silly little mistake, thank you for noticing 🙂
.closed
.close
Closed by @kindred flame
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 if I can scale each vector such that the sum is zero, its independent
you need the concept?
Closed by @quasi turtle
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.
Determine the magnitude of an earthquake with approximately twice the intensity of Tremor
measuring 3.5 on Richter scale?
can someone help me with this?





