#help-38
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Is there any more efficient way to do?
I'm thinking to do with line sketching, but how?
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What are the main topics in Calculus at the start of university? Like is trigonometry the main thing?
This is better for #discussion . Help channels are for math problems
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Ok, so for context i go to a islamic school and we have a mosque in the school. Ok so on friday two previous gradutes form our school came back for friday prayer, after that they came in our class and sat down and made up a story that their grandpa died or something so they ahve not attended school much, then the teacher took us out and somebody told the teacher that they were not part of our class, then the teacher called them and asked them are you from the class and they said yes and then ignored her and then ran off in their car, now the admins are saying that they are going to take 10% overall mark off form the girls and 15% mark off from the boys since somebody didint tell the teacher that they were not from our school when she asked. ( I had not talked to them nor did i go and associate with them) what should i do now since this seems like a problem on the admin that a random stranger came in class and sat down.
pls hlep me although not mah help
I don't think this is a maths question
Sounds like something you should take up with an advisor at your school or something
Or whatever government agency is responsible for education where you live
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Can someone double check my work please? I’m trying to find the derivative of the original equation 2x / 1+x^2
2x•2x ≠ 4x
Would it be like this instead?
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can someone help me?
What’s the probability one die lands on a 2
1/6
What’s the probability one die lands on a 4
1/6
What’s the probability one die lands on a 2 or a 4
1/3
What’s the probability 2 dice lands on a 2 or a 4
You tell me haha, what’s your reasoning
well because if theres an or in the question then you add the probabilities
so
1/3 + 1/3?
So there’s 4 outcomes that we desire: a 2 on die 1, a 4 on die 1, a 2 on die 2, or a 4 on die 2
Do u agree?
How many total outcomes are there?
so 24/36?
nvm i found out what i was doing weong lol
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how to derive $\int \sec{x}dx$
Jash
haylsGhost
Usual way is to multiply by sec(x) + tan(x) on the top and bottom
so $\int \frac{\sec²{x}+\sec{x}\tan{x}}{\sec{x}+\tan{x}}dx$
Jash
then what
u=secx i think
No u
i don't think that will work because what are you going to do with the tan x?
ye so what u do you use
secx + tanx
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so if I have 3 < a < b
which is greater: a^b or b^a ?
idrk where to even start with this, I tried ln on both sides but it didnt rlly give me an answer
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do you know what cis(x) means
yes
ok so we have this right
right
which is this
and we are looking for theta
we dont want to deal with plus or minus
so what trig will relate -i and 1
uhhh pi/4?
tan(pi/4) is 1
oh so -pi/4
yeah
except cis(-pi/4) is sqrt(2)/2 - sqrt(2)/2*i
so how do we get
1-i
sqrt(2)/2*r = 1
actually this is a bad way to do it
so we have this triangle
and we want this
what do we multiply by
you multiple by sqrt 2?
ok right
so we multiply by sqrt(x^2+y^2)
so to convert any rectangular coordinates x and y*i
we do
sqrt(x^2+y^2)*cis(arctan(y/x))
do you understand?
ya that makes sense
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can someone explain to me the justification for doing this part of the step for mathematical induction
original question is (n+3)^2 <= 2^(n+3) where n is an interger n=>1
You want to get a polynomial in the form (k+4)^2. This is the same as k^2+8k+16. If you compare term by term its obvious this is smaller than 2k^2+12k+18.
but how does that justify allowing you to replace it
because I understand replacing stuff from a given like a= 35 so therefore a+b = 5 is 35 + b = 5
It is not replaced. It is saying the 2k^2 polynomial is greater than the k^2 one

If I just said 2k^2+12k+18>k^2+8k+16 you would agree right
yes
oh were following the lines aren't we
OHHHH
wait why was it done there not like earlier
is it because they are similar or...

but why there can we do that
because before we subbed 2^(k+3) in as (k+3)^2
and thats obviously smaller than 2^(k+4)
am I only allowed to compare them when they are similar enough to each other
man
@low gazelle
soz for ping
You can compare them if you can prove one is greater than the other. In the case of 2x^2+12k+18 and k^2+8k+16 though it is trivial
So you dont need to prove it
oh so you only do it when you know one is greater than the other
ahh

oh boy thats going to be hard to see
alright thanks for the help
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help :((
in synthetic division pls
i solved it and i checked it with a calcu, but my answer is diff
how do u do itt
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@quiet oasis Has your question been resolved?
you divided by x+1
you wanted to divide by (x+1)²
how do u write that as a divisor??
with the synthetic division you're doing it's kind of a pain
but you can just divide by (x+1) twice
yea, buts unfortunately its what our teacher want
so just do it twice
wdym
well like
if you divide by 5 and then divide by 5 again, it's like you divided by 25 in the first place
oh so, after i divide it by the divisor and get the quotient, i just divide the quotient with that divisor again??
yeah since you're trying to divide by that divisor squared
imma try it
there's a way to do it all at once but it's just as much effort and harder to understand
yea, our teacher kinda sucks how she doesn't explain certain stuff
WAIT NO WAY IT WORKED
unfortunately common
of course it worked, it's algebra! 
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Question: You have 1 Red candy, 2 blue candies and 3 green candies in a jar. You are taking them ouut one by one, what is the probability that there are at least 1 blue and 1 green candy lfet when you have taken out all the red candies
I've seen the answer is 3/6 * 2/3 + 2/6 * 3/4 but am struggling to understand it
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<@&286206848099549185>
Have you tried drawing a tree diagram?
Not yet, would it have 3 branches initilly?
Aight let’s not draw a tree diagram for this
I just had a better look
The probability that the last of the 6 candies taken out is green would be 3/6
Then the probability that the last of the remaining 3 candies taken out is blue is 2/3
Yh so 2/3 would be blue
Now we can also do it vice versa
That being the probability of the last of the 6 candies being taken out being blue would be 2/6
Then the probability of the last of the 4 remaining candies being green would be 3/4
sorry if it's dumb but why is it 3/6?
Because there’s 3 green candies out of the total 6
For you were to draw a tree diagram, there would be 2 branches because there’s 2 possibilities but idk I wouldn’t for this
why not 1/6 * 2/5 * 1/4 (first red then take out one of the blues then the last bblue) and then the sum of the different combinations ofthat
the probability that last is green is the same as first is green, or 4th is green
it's not obvious but that's how it works
it's not an easy problem to solve or explain
You could Ofc try that but then it would be much longer
ah okok
,calc 1 - (1/6 + (2/6)(1/5)+(2/6)(1/5)(1/4) + (3/6)(2/5)(1/4)(1/3)+(3/6)(2/5)(1/4) + (3/6)(1/5))
Result:
0.58333333333333
It should still lead to the same probability at the end as long as it’s done right
that's what i did to get the answer
that's the right answer woah
You could have many combinations and as long as it’s done right it should be right ^^
You could do a 3 branch tree diagram for this too
But I wouldn’t
So is this 1 - the scenarios where you take out all the blue or green before taking out the red?
ah ok
we fail if we draw red last
also we fail if we it goes ...rbb and if it goes ...rggg
but also ...rb and ...rg and ...rgg
so six things
still look backwards as in the short solution
ah right ofc
Did it make sense?
The way you were going to do it would’ve been right too as long as you did all the possibilities just wasn’t the fastest way
Or do we fail if it's rggg? as the problem said what is the probability that there are at least 1 blue nd 1 green
afterr all the red candies are taken out
Yh so you can’t do rggg
Because we need exactly 1g left at the end
But after you take out the red (assuming it's the first draww) you have 3 green and 2 blue which are both at leaast 1 each?
I meant exactly 1g
You need to keep going until you have exactly 1g and 1b left
If you wanted to do it 1 at a time
You could have rbgg
Or rgbg
it's not the first draw in any of the six cases
Or rggb Or grgb and on and on
you're confusing rggg... and ...rggg
hmm ok
I have to think about this problem some more but thank you both so much for your help
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Is this correct for Gaussian elimination
And if so, are there no solutions because of the last row being absurd?
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ik its physics, but its an easy one, wanted to ask why friction is not acting on the opposite side of friction in this FBD
Please don't occupy multiple help channels.
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<@&286206848099549185>
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!show
Show your work, and if possible, explain where you are stuck.
help me work out in steps
i think it might be the 2nd last and last one but iim not too sure myself @mystic veldt is that correct?
idk
8x8x8x8
also can be written as$(2^3)^4$?
!Yajat!
huhh
,, 2^3=8
!Yajat!
but why the four
cuz this was the question
okay
okay now from laws of exponents can it be written as 2^12
,, (m^a)^b=m^{a\times b}
!Yajat!
thats what i did
nvm i got ocnfused on smt else
so ist 2 with the exponent 12 yeah
i do this exact steps on the 6 one too
what?
,, 6 is already simplified, 6=2 \times 3
so ist 2^12 3^2
no
i dont understand i understood the 2^12 but not the other
wait firsly, let us simplify this term only
then we will jump to the 6 part
okay so now its $\sqrt{2^{12}}$
okay
!Yajat!
how would you solve this?
64?
yea, better write it as 2^6 as the answers are somewhat given in this form
okay
now simplify $\sqrt{6^4}$
!Yajat!
36?
sorry i keep forgetting
yes
so it is now $(2^6 \cdot 6^2)^{\frac{3}{2}}$
!Yajat!
right?
yes
what about you use this now?
okay
9?
yes
aslo 3 on the second one
$2^9\cdot 6^3$
!Yajat!
this your answer now
yes
so isnt that the second last option
yes
yes
no it wouldnt be
why do you think so?
why are you deleting it
if you have a doubt ask it
i over confused myself n i relaised it so i deleted it dw abut that
theres 2 anwser trying to figure out the second one
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Sarah places k objects into n boxes at random (i.e. with equal probability). Given that
the first box is empty, what is the probability that the second box is also empty?
I found that P=(n-2)^k/(n-1)^k but I have a doubt
because when I calculate manually for 4 boxes and 3 objects I don't get the same value that from the formula
i don't understand that formula
why (n-1)^k
makes no sense
oh, you want to place more than one object
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calc// find where the function decreases and increases f(x) = x^(1/3) +1
Hello there I did a proof for L'Hopital's rule for Derivatives of the 0/0 case using the definition of the derivative. One trouble I am having is that I know we have to continously imply L'Hopitals rule till we arrive at a limit that exists, but am trying to figure out the proof for it. Any ideas.
please get your own help channel
So what we are going to do here is observe the concavity of the function.
refer to #❓how-to-get-help
You need to start by observing the critical points.
okay
And then you need to test points within those intervals and determine the sign of the derivative which will thus indicate the behavior.
Set the derivative to 0 or DNE.
so no solution?
Well then its an extraneous solution. Here Ima take a look and work it out.
So when we set the derivative equal to 0 there is no solution. However when we set the derivative equal to DNE we observe that x cannot equal 0.
And that is because our derivative would be infinity.
Now we set up our intervals
okay
first time i’ve heard of setting it equal to DNE
can you walk me through how to do
Interval: x > 0 & x < 0
f' sign: positive and positive
Behavior: increasing and increasing
how’d you find that
Sure, so the reason we also set it equal to Does Not Exist is because it gives us important information of the derivative.
I'll give you an example of a simpler function.
yeah
If we observe this function and picturize a tangent line from both ends as x --> 0 the derivative would be infinity.
But we can't have that as the derivative has to be finite.
And it would therefore not exist.
yes
Now what our concern is the behavior of the function cause our end goal is to sketch the function.
Do you know about conacvity of functions?
taking the second derivative of the function have you learnt that yet?
yea
no
Mk are you a beginner in application of derivatives?
pretty much
Like just on the first unit sketching and analyzing functions?
yes
mk, ur gonna learn abt concavity later.
i think so
anwyays for now.
yeah
You always want to set the derivative equal to 0 and DNE. Remember that because there lies the possibility that a functions behavior can change.
for instance.
okay
Here is the general formula you want to always apply when sketching and analyzing functions. Gimme a sec. Ima write it neatly for you.
alright thank you
np.
ping me when you finish
Follow this procedure if you want to determine the behavior of a function.
I'll probs be busy, but I'm sure someone else will help if thats the case.
Gl wit it. Its quite an interesting unit man.
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How do I prove that hyperspaces are convex but not affine, when I follow the same format as the proof given here it doesn't work
i.e. why must theta be limited to [0,1] in the case of hyperspaces
@true bridge Has your question been resolved?
take a point on the boundary and another point not on the boundary
if you allowed arbitrary affine combinations then the entire line containing those points would have to be in the hyperspace
but that line is not parallel to the boundary, so part of the line is outside the hyperplane
whereas if you consider only convex combinations (theta in [0,1]) then you only consider the line segment between those two points, not the entire line
I see, intuitively I see why however when I try to formally prove it where is the contradiction.
I've allowed theta to be any real number but it needs to tonly be from 0 to 1
Yeah I’m stuck on that part let me just fix up the work and I’ll show where I’m stuck
Here it is idk what to do from where I am at
Was I supposed to use the quotient rule first ?
$5 \left( \frac{x}{x+1} \right)^4 \frac{d}{dx} \left( \frac{x}{x+1} \right)$ chain rule then quotient rule
Master Wanky
@left oriole any updates big bro 😦
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is the top row of pascal’s triangle row 0 or row 1?
ping me if u respond pls
0th row is just [1]
then 1st is [1,1] etc
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Can someone explain to me the definition, foiling, and collecting terms part?
I don't understand how it became
(cos a + i sin a)(cos B + i sin B)
(the doc is proving the cos and sin addition and subtraction rule)
ohh okay....
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hello
how do i find the domain of Arccos(cos(x)) ?
@wind mortar Has your question been resolved?
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A and B are included in U
meaning?
I have to create a larger circle than the venn diagram that represents U?
A have elements of U
think of the universal set as elements you are focusing on
an element is the thing in sets
ok
I cant explain it better than this
Diagram is a little off, A and B share an element
8 is not in both a and b
so where is 8 in the diagram?
Ah ok
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@sturdy holly Has your question been resolved?
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<@&268886789983436800> spam
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isn't it actually -1/12?
Distributive law doesn't work over infinite sums.
why not?
^
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What is the sum of all the natural numbers?! Of course the answer is obvious...right? Many have actually pointed to the result that the sum of natural numbers is negative 1/12 !
We're going to do a 1+2+3+...=-1/12 ...
Just watch this, it'll be pretty hard to explain without any visuals.
is there a stack exchange page with that property or whatever u call with distributive thingy not working over infinite sum?
in addition to this ofc
I can't really prove it tbh, it's an assumption.
no not you
do you know what it’s called
I don't really know, sorry.
But there are also multiple evidence that proves it's wrong
Confused 1+2+3+…=-1/12 comments originating from that infamous Numberphile video keep flooding the comment sections of my and other math YouTubers videos. And so I think it’s time to have another serious go at setting the record straight by having a really close look at the bizarre calculation at the center of the Numberphile video, to state cle...
here, he is using the distributive property
not the distributive law, i'm not really sure about that
lol i just noticed too
to show that it's wrong.
oh, yeah... i didn't watch the whole vid
there are multiple videos and articles that has debunked all of those "proofs"
just search it up.
right right so basically the takeaway is infinite distributive law doesn't hold if the series doesn't converge
didn't quite get the riemann zeta part though
yeahh
like okay i get that we're using it beyond the domain it's defined for but hmm
analytic continuation?
okay nice video
thanks @warm kernel @quasi wasp
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Hey guys im dealing with languages and regular expressions as well as regularity and irregularity.. In the first screen shot we prove the language is not regular via pumping lemma. However in the second screenshot the language satisfies all these definitions thus resulting in a regular language?
the second thing is talking about a regular expression, and I don't see one for that language
What if I were to use this method instead. Try to come up with a regular expression for my language
try it!
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Did I verify this right? Or Do i have mistakes?
Haha what a coincidence
..
how did you get to the third line?
fourth equality i mean
That's where i went random Haha
Dunno what i'm doing
I tried trial and errors But i can't find a suitable one
Hmm?
So Like it would be 1+cosx/1-cosx?
explain to me the fifth and sixth equality
I just tried my best to come up with that.... Thats my explaination
Idk also why icame up with that
Haha
I'm dead at trigo
try doing the common denominator right from the beginning
With Sine?
without replacing csc and cot
here it is how i would've solve it
sorry for the handwriting , i know it isn't the best i've got alot of complaints
No no... You've helped Me a lot
I'm thankful
Ohhh @wraith hinge you used phytagorean
I didn't know you can use it here
Hahahaha
Thanks
john.
if you devise the whole thing by sin^2 you get the identity that i have used
if you devise it by cos^2 you get 1+ tan^2 =sec^2
and i have used (a-b)(a+b)=a^2-b^2
Ohhhhhh
I see
Imma learn It tom
Now I sleep
Hahaha
Thanks For helping me Dear same name
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can sombody help me about how to integrate this liner over quadratic?
So this is your integral: $$\int \frac{1-x}{(1+x)^2};dx$$
Good
Are there any thoughts that you immediatly came up with when looking at this integral?
yeah but nothing worked
If you got the integral:$$\int \frac{x}{(1+x)^2};dx$$ How would you solve for it?
Good
maybe by parts
Alright, that might be a way. But what if I asked you to do substitution integration?
Will it be a way for you to solve it?
Have you learned about substitution integration before?
yes
How does substituion integration work?
something like u= 1+x then du= 1 then you replace and such...
Alright: $$\int \frac{x}{u^2};du$$
Good
You're on the right track. But how about x? What could you do to make it u? If u = x + 1?
x= u-1
I'm not bad at math i took B= in calclus 1 and 2 but it is been a long time since i solved a question
I forgot some of the rules
thats it
This is your algebra intuition. But is that really true if we convert u to x again?
Our u is x + 1, when making u to x again, you get x + 1 - 1, which is just x.
But that doesn't seem as what u is that we defined before, which is u = x + 1.
The point here is converting u and x. Our definition is u = x + 1, which means when we convert u to x again, we want x + 1.
okay
If u = x + 1, then the numerator is missing the 1.
what does this has to do with the problem I gave you
just give me an example that would be easier as english is not my mother tounge
The question you gave is related to substituion integration.
the square is just on the x not the whole x+1
Good
Then it's part integration that you mentioned.
With the concept of the example, do the same with your question.
so my main problem is integration by parts?
without supstitution
becuase it already looks like this
I can't use substitution on it
I'm not sure if you could just dive into part integration, but it seems expect you to use substitution integration initially.
I tried and it didn't work
What if I did this instead? $$\int \frac{1-x}{(x+1)^2};dx$$
Good
Are there any thoughts now?
why do you keep putting the square on x+1
it is only on x
here I could just use partial fraction after playing with x+1 squared but that is not my problem
My bad, I saw you used parathesis, so I thought it was (1+x)^2 the whole time.
So this question involves solving two integrals, meaning you're going to split the integration to two.
how can I do this
Just like fractions $\frac{a + 1}{b} => \frac{a}{b} + \frac{1}{b}$
Good
there is a + constant on both sides
What do you mean by that?
$\frac{a - 1}{b} => \frac{a}{b} - \frac{1}{b}$
Good
$$\int \frac{1-x}{1+x^2};dx$$ $$=>\int (\frac{1}{1+x^2}-\frac{x}{1+x^2});dx$$ $$=>\int (\frac{1}{1+x^2}); dx - \int (\frac{x}{1+x^2});dx$$
$\frac{b - 1}{b} => \frac{b}{b} - \frac{1}{b} => 1 - \frac{1}{b} $
THE SQUARE IS ONLY ON THE X
what makes me satisfied?
That I finally did it correctly.
thanks for the help
forgive me
I'm al little bit stupid
sorry for speaking to you like this
All fine, it was my fault that I didn't see the expression correctly.
the first is tan invers and the second is substitution right?
Thank you for your time and sorry again for being rude
Good
All fine.
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How does this work?
This algebra video tutorial provides a basic introduction into natural logarithms. It explains how to evaluate natural logarithmic expressions with the natural base e and how to evaluate exponential expressions with natural logs in on the exponent of the natural base e using properties of logarithms. This video contains plenty of examples and ...
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The mean and variance of the hypergeometric distribution $\map h{x;N,n,k}$ are [
\mu = \f{nk}{N} \tss{and} \sigma^2 = \f{N-n}{N-1} \cdot n \cdot \f k N \parens{1-\f k N}
]
i am trying to prove this but i really have no idea 
do you know the formula for the pmf?
can u show if u can
oh probability mass function
yes i do
wait
[
\map E X = \sum_{x=0}^m x\f{\binom k x \binom{N-k}{n-x}}{\binom N n}
]

so like
ugh i have to remember some combinatoric bullshit identities dont i
okay one sec
It's usually just a matter of absorbing the x into the n choose k terms and then splitting it into up or changing the indices in such a way that you have something multiplied by a known probability distribution. These kind of problems are not really that enlightening in my opinion
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oh i see lol
set $z = x-1$, [
\f{nk}N \sum_{z=0}^{n-1} \f{\binom{k-1}z \binom{(N-1)-(k-1)}{n-1-z}}{\binom{N-1}{n-1}}
]
i think 
so you just get nk/N
oh wait
ok so thats neat lol
thanks doe
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In measure theory, I want to find the lebesgue measure of the interval [0,1] without the numbers in which 7 appears in the first second and third decimal place
So with regards to the first decimal place I have an interval [0,0.7]U[0.8,1]
For the second decimal place I have [0,0.07]U[0.08,0.17]….
And similarly for the third decimal place
Where I have unions of 2, 11, and 101 intervals respectively
How do I combine these to get the total lebesgue measure in this case
might be easier to find the measure of the complement of each
for the second decimal place, group the intervals into equal sized lengths
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mb
So we’re looking at the interval we’re discarding, namely 10 intervals of length 0.01?
So in the case of the first decimal place, we’ve discarded an interval of length 0.1, for the second decimal place we’ve discarded 10 intervals of length 0.01, and for the third decimal place we’ve discarded 100 intervals of length 0.001
@sudden lagoon Has your question been resolved?
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if your number has 7 in the first, second, and third decimal place, you can write it 0.777... with ... meaning whatever after
unless you meant or
I meant or, apologies
then you can follow riemann advice
the number 0.7... are [0.7, 0.8[ so 0.1 of measure
then the number 0.x7 are [0.x7, 0.x8[ are of measure 0.01, and we count them for x = 0, 1, 2, 3, 4, 5, 6, 8, 9 (we already counted for 7)
so the total measure is for now 0.1+9*0.01
and you do the same for the third place
and you subtract that from [0, 1]
And the third place we’d have [0.xx7,0.xx8] of measure 0.001
Where neither position contains an x?
where neither x is a 7 yeah
since we already counted for 7 in first and 2nd
the xx can be 00, or 01, or ... 06 or 08 etc
81 choices
yes
also, there is another way of counting which was combinatorics, but I assumed you wanted to calculate some measure bc it was measure theory
Yea no you’re right, and it completely makes sense
I think again for today you’ve been a great help, thanks a million!
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- I have an answer and I want to know why it's wrong
Show your work, and if possible, explain where you are stuck.
if X=number of diesel cars, we are looking for P(x>1), wich is equal to 1-(P(x=0)+P(x=1)) since we have 5% chance to have a diesel car, Poisson's probability is 0.05*4=0.2. I think my Poisson's probability is wrong though since my answer is 0.001209
here is what ive done so far
the number of Diesel's among 4 already filled spots car follows binomial distrib since it's a repeated independent event with a probability of 0.05
uhm intersting
how can you describe the binomial probability? x\sim B(4,0.05) or x\sim B(4,0.2) ?
yup i think i have it
i have 0.014018749999999
it's correct!
i'll go on with the 2 other problems
@wraith hinge Has your question been resolved?
it was still not poisson for q2
how can you tell if its poisson or not?
you're looking for a probability of first success, it's geometric
i think thats the issue
the probability that an appearing car is a diesel car is 0.05 for each car that comes, the cars are independent
and they ask for the probability that to see at least 15 cars to see a first diesel car
so they're asking for P(X >= 15) where X follows a law of first success
the law that describes this situation is called geometric distribution, and is the discrete equivalent of Poisson
ok i'll try again
first question is right though
oh yeah ?
yes
the question is weird
bc there is only one spot for diesel at the gas station
so it's impossible that 4 cars at the gas station needs diesel
we could have interpreted the probability to be 0
yes, that's what i initially thought, but they could be at the gas station but not refuelinh
yeah I guess, that was ambiguous
for a sec I thought the question was a troll after reading for the 4 spots
i saw it comming tried it first and lost a couple points
oops
is the geometric law for probability : p(X>=x)=(1-p)^(x-1) ?
yes
I find 0.48765, around that
oh yeah
i found it too missed my formula
it's correct!
Last question now
i have an average profit of 1369,50$
that's way too much
there are 66 cars per hour
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I don’t know what I’m doing wrong
I don’t know what I’m doing wrong
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how could I prove that the set is closed under addition? It makes sense that a linear combination of orthogonal vectors would also be orthogonal but I am unsure how to convey that mathematically.
you know that, say, $u_1 \cdot v = u_2\cdot v = 0$. to show closure under addition, you need to show $(u_1 + u_2) \cdot v = 0$.
gergill
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I am having trouble understanding this problem. Not quite sure how to find Q
@rare fox Has your question been resolved?
@rare fox Has your question been resolved?
@rare fox Has your question been resolved?
Find the slope of the secant line first
yes
or wait
whats a?
Mpq = gradient of the secant line
not sure where you got a from
a is 2?
okay good, thats p
as for q, you substituted x = 2. that would just be p again
x values of q are given, they are not 2
you’ve basically tried finding Mpp which is undefined on a curve
Oh
Also is it even possible to find Q since the point (0,2) was unintentional. I just was working on it, no point was given besides P
P is given as (2, 0)
Q is given as (x, f(x)) ( cuz if x coordinate is x, y coordinate is f(x) as y = f(x))
youre given x values in the table. substitute them and find the corresponding y coordinates for Q if that is your x coordinate. then find the gradient (Mpq) between P and Q
using your formula, which is correct. except a = 2, f(a) = 0, which is P. x = whatever the table says, and f(x) you can find
f(x) = 2- 1/2x^2 ?
as given, yes
So Q can be (1.5, 2-1/2x^2)?
yes but if x = 1.5, what is 2-1/2x^2?
Ohhh, so 0.875?
(1.5,0.875)?
