#help-28
1 messages · Page 193 of 1
then you do (x-(5))
(x-5)
you translate it 5 units to the right
to come to -3
one sec
lemme do it on the mssage
3(2/3(x+2)^2-7 -----> -3(2/3(x+2)^2+7 ----> -3(1/9(x+2))^2+7 ---->-3(1/9(x-3))^2+4
-3(1/9(x-3))^2+4
is my answer
key says instead of (x-3) its (x+7)
im not exactly sure
since right C units is -C in this form
x+2-c c=(5)
X-3
🤷♂️
after you do -f(x) you do -f(x/6) so you would get
-3(2/3(x/6+2)^2+7 factor now intead 1/6
-3(1/9(x+12)^2+7
Now do (x-5)
-3(1/9((x-5)+12)^2+7
becomes
-3(1/9(x+7)^2+7
you didn't factorize correctly
2/3 is not only being multiplied with x/6 but also with 2 if you choose to expand it
no problem
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Find the number of pairs $\left( p, q \right)$ where $p, q \in {1, 2, 3, 4}$, and there exists a real number $x$ such that
$$x^{2} - p{x} + q = 0$$
\textit{Note. The notation ${x}$ represents the fractional part of $x$}.
raymondclie
I guess you can do D≥0 for roots to be a real number
D is discriminant
What do you mean
Well a quadratic equation is given , x means root of equation.
For x to be real, discriminant D should be greater than or equal to 0
You know roots of quadratic equation formula?
Ohhh what's {x} ??? Is p{x} different than px?
Yes, of course, {x} denotes the fractional part of x
$0 \leqslant {x} < 1$
raymondclie
Ohhhh mb then, ignore my suggestion. Wait for some other helpers
Alright
i think here cus we have such a limited number of possibilites we can effectively just exhaust
How so
wait hang on
right so i think you can basically use the fact that {x} = x - \floor(x)
so if x satisfies the equation u've written
then x^2 - px + q = integer
so x is a root of x^2 - px + q+stuff
and then you can probably get bounds on x
so it doesn't work for a lot of values
hmmm
$$x^{2} = p{x} - q$$
Since $0 \leqslant {x} < 1$, we know $ 0 \leqslant p{x} < p$. So,
$$-q \leqslant p{x} - q < p - q$$
raymondclie
@sly carbon Has your question been resolved?
<@&286206848099549185>
roots of x^2 - x - k are 'approximately' sqrt(k) but we need to shift by k
so we'll never get any more
u can probably do something similar for p=2 and p=3
Observe the equation, what you have is $x^2$, we know that $x^2 >=0$ for all real values i.e
$ p{x}-q >=0$
or since p,q > 0 and the maximum value that p{x} can take is {x} = 1;
for now i know that
p = q = 1 doesnt work
(p, q) = (2, 2), (3, 3), (4, 4) works for x = 0
in fact, if our original quadratic x^2 - px + q has a root between 0 and 1 it works too
you can plug in x=0 and x=1 to discover that
i cant even read this
ZaNXar2315
man
(2,1), (3,2), (3,1), (4,4), (4,3), (4,2), (4,1) all work
how did u get (2,2) and (3,3)
p = 2, q = 2
x^2 - p{x} + q = 0
x^2 = 2{x} + 2
x = 0 works
$x \in \mathbb{R}$ so it works
raymondclie
basically the solution is find all p,q where p >=q
why?
Analogously for p = q = 3, and p = q = 4
0 = 0 + 2?
@sly carbon
fractional parts cant be 1
$0 \leqslant {x} < 1$
raymondclie
raymondclie
oh god i choke latex so bad
You mean
Observe the equation, we know that $x^{2} \geqslant 0:\forall x \in \mathbb{R}$ i.e. $p{x} - q \geqslant 0$. Since $p, q > 0$
raymondclie
for all p > q it the equation should hold true
and we already have that it works for all p > q
ignore this i made rearranging mistakes
I got $p \geqslant q$ from:
$$x^2 - p{x} + q = 0$$
$$\implies x^2 = p{x} - q$$
Bound
$$-q \leqslant p{x} - q < p - q$$
Since $x^{2} \geqslant 0 \implies p{x} - q \geqslant 0$
$$p{x} \geqslant q$$
$$p \geqslant q$$
raymondclie
$p \neq q$, right?
raymondclie
leqslant or leq for =<
geqslant or geq for >=
how does (4, 4) work?
yeah
no bcus of this
what does maximum value that p{x} can take is {x} = 1 mean
they were just saying that p{x} < p
yea
x^2 - 3{x} + 3 = 0
x^2 = 3{x} - 3
oh yea
its obv
n{x} < n
my bad for not realizing
alright no solutions for all p = q
how so for p > q
plug in x=0 and x=1
and is this correct?
=> root between x=0 and x=1
alright, noted.
ill just write it on my proofs then make it p > q, after showing n{x} < n
thank you
i checked with wolfram
(2, 1), (3, 1), (4, 1), (4, 2) all have real solutions
not (3, 2), (4, 3)
no output for (3, 2), complex solutions for (4, 3)
does (3, 2) and (4, 3) not have real solutions, i checked with wolfram
oh (2,1), (3,2) and (4,3) don't work because 1 is a root
how tf did u get complex
idk lol i used wolfram
for (2, 1)
x = 1?
x^2 - 2{x} - 1 = 0
x := 1
1^2 - 2(0) - 1 = 0
1 - 1 = 0
(2, 1) works
x^2 - 2{x} + 1 = 0
x := 1
1^2 - 2(0) - 1 = 0
1 - 1 = 0
wait is it the
this right?
yeah so u might have to use that to see if there is some weird construction that does work for (2,1), (3,2) and (4,3)
yea, i checked with wolfram
no solutions for all 3
(3, 1), (4, 1), (4, 2) does have solutions
thank you so much
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can someone help? idk how they got the y=1
Denominator is zero when?
x is 1 or x is -3
Oh it's the limit as x goes to Infinity
yea
the asymptotes r
those
but i dont understand
the y=1
@gritty rose
wait nvm
it wa sjs a typo
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having issues with this problem, I'm not sure what it wants me to put. I thought it was the difference quotient, but it doesn't accept that as a correct answer. What am I missing here?
,w Expand[ (7-(x+h)^2) - (7-x^2 ) ]
@rugged laurel does that help
this is the numerator of the difference quotient
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he chose to add the terms on the right side to the left instead, it doesn't really matter which way you do it
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is this correct
Well, first, notice you're multiplying a degree 3 a degree 2 and a degree 1 polynomial
yea
The degree of the result is the sum of those
so adding not multiplying
Yup
so 6
Yup
And for the y intercept
All you've gotta do is set x=0, so the y coordinate will be (2)^2 x (-4)^3 x (-3)
That'll give ya the y, but as you probably can see, it'll be positive and greater than 192
Yup
(0,768)
With what?
And yeah, that's the y intercept
i think i understand was just confused for a sec
Alright, first of all the x intercepts are points for which the function equals 0
So what I'd do is actually equal it to 0, and solve for the possible values of x(it's easier than it seems)
That'll give you both the number of them and their coordinates
there would be 3
Yup
(-2,0) is the other?
Yes
It's the same question, isn't it?
And I'm totally sure your answer's righr
The x intercepts are the same
This is your graph
Exactly 3 x intercepts, with the coordinates we said(that gray point near (3,0) isn't an x intercept, just is close to kt
i have no idea what im doing wrong
If I'm being honest, I've no idea either
As you can see above, your answer is correct
Exactly three intercepts, and with exactly those coordinates
Worst case send em the graph
yeah im so confused
,w plot (x+2)^2(x-3)^3(x-4)
huh
am i tripping
what the hell did I type in wrong
guess the y scale is too high
if we go by specifically crossing the x-axis that's not true for x = -2
Probably too zoomed in, cuz I also graphed mine on desmos
The question asks for x intercepts
They clearly want points for which the function equals 0
Number of x-intercepts at which f crosses the x-axis
Obviously at x = -2 it's not crossing
i just did (3,0)(4,0) and its still wrong
Alright, didn't notice that part of the question
Quite sneaky to add that to an otherwise typical exercise if ya ask me but whatever
what did i do wrong in that question
The question's asking you for points in which the function touches the x axis
I am noticing here it says flattens out
And then changes sign
so it would've just been (-2,0)
So the multiplicity of the root is even.
omf this is so annoying
At least that's my interpretation.
I swear, I hate poorly written questions
Ain't no way we've been here for ~10 minutes just because the guy didn't make clear what he was asking

thanks yall i wouldn't have gotten it
But what's wrong with this part?
Np(though for this last part I may've made it more confusing, really)
there were 2 answers
What is the second?
i was too zoomned out
She wrote -3 there
Nvm, the function changed again, istg
I guess it keeps changing, when you fail thrice
(x^2-3)=(x+sqrt(3))(x-sqrt(3))
Yup, sorry
Says “factor completely“
Which is quite ambiguous
see this one of those things where i would be confused
but i agree with your argument technically
i tried one similar but got it wrong so idk
but i have a feeling it will be wrong
yeah idk what else it would be
We're basically playing mind games with her teacher, I swear
i think im wrong tho
Yeah, let's hope her original answer was right
but idk what it would be
else what prim suggested
that?
you are missing the other two factors
Times the other factors
this just simplifies to x²-3 
I think imma go to sleep btw, you should be able to help her out just fine
Good luck with it to both of you
true
but you are missing (x-5)(x-3)
[ \textcolor{cyan}{(x^2-3)} (x-5)(x-3) = \textcolor{cyan}{(x+\sqrt{3})(x-\sqrt{3})}(x-5)(x-3) ]
This was what Prim was pointing out to do, as the task suggests to factorize completely.
oh
bacc
As obvious as it gets.
I actually think you used a calculator anyway 
degree should be obvious here
stop sayinf that i keep getitng confsued wether i multiply or add
huh
obvious
you just look at the biggest power
what
It was in the form of linear factors
(x-1)(x+2)² for example
here you would need to multiply everything out
for the degree
i swear it was the same typa problem
bacc
This is the rule he meant, but only because you need multiply the stuff out to figure the highest power
Here in this example you can already tell the highest power, and that is x^4
Nothing can be expanded as opposed to the previous example
so the degree is just 4
yes
A polynomial of 4th degree.
Now for the y-intercept you literally do f(0)
and then your ordered pair looks (0, f(0))
-45
ok yay
would this only be 2
when i graph it two of the points are like 1,546464
theres 3,0 and 5,0 so would it only be those two
All of them linear factors have an odd degree n = 1, so they all cross the x-axis.
so what would i round it to
You can see it here too, that all 4 x-intercepts cross.
round?
i wouldnt?
It says to choose the amount of x-intercepts where f crosses the x-axis
Where does it say to round?
It's 5 am dont play games with my mind lmao
You select the amount of x-intercepts that do that
it dosent let me put that nuber in
I dont understand you
so theres only 2
No
You can literally see what is going on
?
can't you select this?
On the left, is there no square root symbol?
then use it
uh how
i dont have your hands unfortunately
bacc
is that form not possible?
😂 almost
bacc
yay
1.5784 what lmao
lmao im in the wrong math class idk how to do any of this
damn girl
what
i mean damn girl
the hell does that mean
you are taking a test or some and you say you dont know anything
that's tough
is this none
ye
they put me in the wrong math im supposed to be taking college algebra
is that harder?
oh ok
youre supposed to take algebra before precalc
well dont worry we will get you through
3?
what
Result:
432
yea def. not
idk what im doing
-3 and 1 correct
is that the only ones
ye
wrong
it says counting multiplicity
oh
-3, 1, 1 should it be
3i,-3i
guess so
I think it's only about real zeros...
what.....
try -3,1,1
yes
-1,-1,1,3i,-3i
shut up lmao
like you
boy what
wym
oh wow so sweet thanks
Damn it's vegito the goat
hi
are you good at math
Maybe
do me a favor
r u leaving
I'm in calc III
no
excuse you
or call you bitch when you say something cute
that's ok dear, good night
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i put this in desmos but it was hard to find the values
idk if this is right js wanna make sure
If you're using Desmos, they can easily give you each of those points if you e.g. click after plotting it, and type them in
i put in a function, can i js click around the relative extrema n it will tell me the coordinates of them?
Yep, for example
ohhhh okay tysm
I shall leave it to you to try the last one (because it's not what you have) 
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Suppose ( p ) is a limit point of ( A \cup B ). If ( I ) is an open interval containing ( p ), then by the definition of a limit point, ( I \cap (A \cup B) \setminus { p } ) is nonempty. Therefore, it contains a point ( x ). Then ( x ) is in ( I ) and ( x \in A \cup B ), and ( x \neq p ). Since ( x \in A \cup B ), either ( x ) is in ( A ) or ( x ) is in ( B ). In the first case, ( x \in A ). Then ( x ) is in ( I \cap A \setminus { p } ), so ( I \cap A \setminus { p } \neq \emptyset ). Therefore, ( p ) is a limit point of ( A ). Similarly, if ( x ) is in ( B ), ( p ) is a limit point of ( B ).
there is something wrong with this proof I can't find it
whoops
You can't conclude that p is a limit point of A until you've checked both cases.
could you elaborate please I still dont see it
The structure of what you need to prove is $(\forall I(I \cap A \setminus {p}) \neq \varnothing) \lor (\forall I(I \cap B \setminus {p}) \neq \varnothing)$ while what you've proven is $\forall I(I \cap A \setminus {p}) \neq \varnothing \lor (I \cap B \setminus {p}) \neq \varnothing$.
what is BA
Morrow
A typo :)
You've shown that for each I there's some x that works for either A or B, while what you need to show is either (for each I there's some x that works for A) or (for each I there's some x that works for B).
Why cant the I be the same for both?
The issue is that some Is are (potentially) only going to get an x that works for A while other I s will only get an x that works for B.
but from the definition we know p is within I so why does it matter if x only works for A or B as long as p is in the same A or B
The problematic step in your proof is "Therefore, ( p ) is a limit point of ( A )."
In order to conclude that, you must prove that for all I containing p, the set I ∩ A \ {p} is nonempty.
That means, you must take an arbitrary interval I containing p and show that there is some x in I ∩ A \ {p}.
You used the given to show that there is some x such that either x is in I ∩ A \ {p} or x is in I ∩ B \ {p}. At that point you're stuck, because what you need to prove is that I ∩ A \ {p} is nonempty.
You can try instead to prove that for all I containing p the set I ∩ B \ {p} is nonempty. You take an arbitrary interval I containing p and wish to show that there is some x in I ∩ B \ {p}. You get your x from the given and run into a similar problem.
You cannot take an arbitrary interval I and show that either I ∩ A \ {p} is nonempty or I ∩ B \ {p} is nonempty. That's not an equivalent statement.
$\forall z(P(z) \lor Q(z))$ is not equivalent to $(\forall z, P(z)) \lor (\forall z, Q(z))$, in general.
Morrow
thank you so much I have been stuck in this for longer than I would care to admit
Glad I was able to help
analysis is a b*tch lol
one that keeps you coming back for more, hehe
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I'm trying to prove
For any random point P on Circle O
angle PAO will ALWAYS be less than or equal to 90 degrees
When A is a point outside circle O
Does anyone have an idea on how to approach this? Anything would help!!!!
Right beacuse when a triangle is an Isoscles triangle, The two same angles can't be over 90 degrees, as if it were, it can't be a triangle!!!
right!
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✅
Hi sorry! one last question
How would I use the isoscles method if point P was touching the circle?
As line segment AP would be touching the circle
do you wonder about the case where AP is a tangent line ?
if an angle of a triangle is 90 degrees then the other two must be stricly less than 90
o h.
OOOPS.
why didn't I think of that!!! silly me
Thanks again, it helped a lot!!
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Need help understand how to approach:
?
So it doesn't converge then, that makes sense to me as well. Wolfram Aloha thinks it doesn't though, which is odd.
So what would be enough reason to prove this.
That lim x to 0 (from positive side) goes to inf?
?
wolfram said it diverges
which means it doesnt converge
why is that odd?
@stuck patrol Has your question been resolved?
Okay i see to miss understand wolframs answer
Instill need to give a reason why it diverges
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find the volume of a cone with radius r and height h, using integration
how do i start?
draw a graph first
you know element taking?
take disc elements
what is element taking?
? sorry i might know this might i dont really speak english
i mean taking elements
maybe i use similar triangles?
like where u take a disc of thickness dx at a distance x
oh idk this then
i know that i should let the tip be 0,0 and find S(x)
oh wait
i got it
nvm
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I'm lost
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Why do you have to multiply by the reciprocal when dividing fractions?
imagine dividing a value by 2, this equal the value being multiplied with 1/2, wich is the reciprocal of 2.
lets take 50
50 / 2 = 25 and 50 * (1/2) =25
thats how fractions work
yeah you need to balence the equation
@trim gazelle Has your question been resolved?
Oh i see so like if you divided by 4
then 1/4 = /4
but u would multiply with 1//4
and divide with 4
so 50/4 = 50 * 1/4
yes
that makes so much sense now
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Can someone explain please? I don't understand why the first sum converges and the second sum diverges... arent they both telescopic series?
In the first series if the sum is taken till n terms, you get 1/2 - 1/(n+2)
To which if you apply limit n—>infinity, you get 1/2 as 1/n+2 becomes 0
But in second one, sum upto n terms is log(n+1) - log1, to which if you apply limit n—>infinity, you get infinity as log(n+1) goes to infinity
Okay makes very sense now
Thanks very much 🙂
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to answer this question you have to rewrite the equation 2x + y = 6 into y = mx + c
which gives you y = -2x + 6 for the line thats parallel to the line you actually want
then you put that with the values 5 = -2(2) + c to find the equation of the line no?
what 2x2 + 5 = c?
yea now put c here
the thing that im wondering is I must've done something wrong because
oh no nvm
im tripping
use the given line to obtain slope which will be the same for the line we require
and now use point slope form
yeah c = 9
yea put that into 2x+y=c
(y-y1)=m(x-x1)
well its asking for the equation of the line
you just found c
put c=9
you should be fine both the ways ig
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u * dx = u , but u' * dx = du ? I guess because u' = du/dx so dx cancel but why u * dx = u . does someone understand?
wouldnt u * dx = u * dx
its from writing formula for partial integration starting from product rule
The notation in the red box is trash
Don't do any of this
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Anyone able to help with Instantaneous Acceleration?
around t=35 v is practically a straight line, getting the slope of said line should be sufficient for your acceleration
in general you can just draw a tangent line and find its slope though if you dont have the function
How does that work/
Find the slope of that line at t=35, rise over run
Its a single point on it though isnt it?
apparently -8.5 is the instant velocity
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You said that the last time too
$\int 4e^x\sin(y)+4y dx = 4e^x\sin(y) + 4xy + h(y)$
wrt which variable?
Derivative
x
yea i see now 😄
for M(x,y)
$F(x,y) = 4e^x\sin(y) + 4xy + h(y)$
Derivative
yeah but chances are its the last one
You just said that lol
yes
but maybe it is wrong 🤣
and im just stupid
so now i need to find Fy(x,y) (partial derivative with of y)
So you differentiate this wrt. y and equate it
and solve for h(y)
$F_y(x,y) = 4e^x\cos(y) + 4x + h'(y) = 4x+4e^x\cos(y)$
Derivative
So h'(y) = 0?
forgot the constant?
no I said h'(y) was 4 - 4y
i made a mistake on the differentiation
it wont happen again 🫡
thanks again you are a life saver as usual
🫡
Of course (I literally did nothing)
moral support is adequate
You too.
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I wanted to confirm that I am doing some math right.
I want to calculate the probability that a person shares a birthdate (year + day) at least someone else in a group of 38,313 people. Assuming 80 year period with equal distribution of years and birthdays:
Probability that the person shares with another individual at random: 1/(80*365) = 1/29,200.
Probability that the person does not share with another individual: 29,199/29,200
Probability that the person does not share with any other individual: (29,199/29,200)^38,313
Probability that the person shares with at least someone else: 1 - (29199/29200)^38313 ~= 0.7307?
you want the probability for one specific person? not just the probability that some 2 people share a birthday?
Yes. In other words that is the probability that bob has the same birthdate (not birthday) with at least one other person
ignoring leap years that looks ok
but if bob is part of the 38313 people then it should be 1 - (29199/29200)^38312
oh yeh true you are right. Should subtract one to not include bob himself
Also as well it is correct to say that around 73% of people in the group share a birthdate with at least one other person?
if you want to incorporate leap years (which seems reasonable (or maybe not idk)) you can just add 20 to the total days
probably not true
Any specific reasoning why not? Seems like if you have a 73% chance then overall there should be 73% of people in which this holds true?
it sounds reasonable to me but i need to think about it more
Well I am in no rush
ok i think i will have an answer soon
yea
i agree with 73% (approx) of people will have a shared birthday
Okay. Ill probably think about it more myself and ask clarification from others as well but best i can tell it is correct
i think it's just linearity of expectation. i also just simulated and am getting 73%
oh right i should write a python program to simulate it that would be rather easy
from collections import Counter
ppl_amt = 38313
days_amt = 80*365
days = [randint(0,days_amt-1) for ppl in range(ppl_amt)]
A = Counter(days)
def check_shared(i):
day = days[i]
if day not in A or A[day] == 1:
return 0
return 1
N(sum(check_shared(i) for i in range(ppl_amt))/ppl_amt)```
it's in sage but close enough to python
just remove the N
i always do that when i can to make sure my math is right
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ΔABC is located at A (2, 0), B (4, 4), and C (6, 3). Zackery says that ΔABC is an isosceles triangle, while Verna says that it is a right triangle. Who is correct?
geometry
Do you know how to check whether a general triangle would be isosceles/right-angled?
nope i forgot
Do you know what an isosceles triangle is?
yes
i put it in a graph and it is a right triangle. Verna, because segment BC is perpendicular to segment AC
Verna, because segment AB is perpendicular to segment BC
Im just confused on which one it is to prove its a right triangle
Well, which pair is the perpendicular one?
(and are those the options given to you? It is possible that both of them can be right - see 45-45-90 triangles, which are both isosceles and right angled)
This is what i got
Result:
-12
(you might want to show your work though...)
No what im saying is i dont know if thats correct or not. I just know its a right triangle and only one is correct
Well, show the plot you have, and which one you think is a right angle, then...
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Im having trouble proving the following formula (the one at the bottom of the proof-tree). I think this is akin to proving de morgan's law for the negation of a conjunction (but with added negations). Im really not sure where to go from here, or if thats even a good start. Tagging @narrow cradle because you helped me earlier with a similar topic. Thanks!
maybe something like this? but it seems like a dead-end...
natural deduction with gentzen tree-proofs, its entry-level stuff but Im having a hard time wrapping my head around it
yeah youll be fine dw
@compact sonnet Has your question been resolved?
You'll need some form of classical logic here since that implication doesn't hold constructively.
What rules does your system have other than the usual introduction and elimination rules?
AFAIK, these are all the rules
so, those are the usual introduction and elimination rules I imagine
Ok, calling double negation elimination (the rule in the bottom left) just negation elimination is a little evil
But that's the key here
Leaving out that rule you end up with the intuitionistic logic where what you're trying to prove doesn't hold
ok, so the double negation rule is the classical logic part I see
So a hint would be to try and prove the double negated form of your goal statement
hmm ok that will help. I will give it a shot and get back to you if Im still having issues
I must thank you, your help has been greatly appreciated
just to be sure, you mean starting the proof like so?
Ah, no you still start out like you usually would with implication introduction.
I.e. assume ¬(a ∧ ¬b), prove ¬a ∨ b.
Double negation elimination will help you prove ¬a ∨ b, since you may prove its double negated form instead
ahhh ok gotcha, thanks
is someone here online?
@narrow cradle
phew what a brain-teaser lol
but I think that's right
thanks for setting me on the right track!
Yep, that looks right! 
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Is this correct? Can someone help explain please?
Which part?
The solution
Where is the first part of the solution you don’t understand, though? Or do you not get anything at all they’ve said?
Are you aware of how you’re meant to construct the matrix of a linear transformation with respect to given bases on each side?
I’m not rly getting anything over here
Couldn’t understand lecturer, the professor’s English is horrible
They're correct and they already explained it well
I’m not sure how a R2 matrix transfers into R4 matrix
You can also just ask them lol
Shortly, You can just think of n as the numbers of the row
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Can anyone pls help me it’s math hw
Anyone can help me?
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-5 7/8 + (-3 3/14) + 5 7/8
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does e^x^2 = e^2x
(I'm rlly asking if the only difference is when it's LITERALLY e^(x^2)
e^(x^2)=e^2x implies x^2=2x which is not always true
i think you have an ambiguity in notation; e^(x^2) is not necessarily equal to e^(2x), but (e^x)^2 = e^(2x).
(e^x)^2=e^(2x) however is true
yeah (ambiguity/I have..) when it's ONLY e^x^2
so ye
I can re-write it as (e^x)^2
yeah you can write e^(2x) as (e^x)^2
ye
so it will alwyas be equal
in that context
if not "specified"
or not written as e^(x^2)
yeah they're the same expression (do you know why?)
e^x^2=(e^x)^2=e^2x
e^(x^2) is just not gonna change
cause parenthesis encapsulate the square on x I suppose
I just know it can't-
y
hey
hey
y
y cant I move ^2 out of the parenthesis
you're asking why e^(x^2) is not always equal to (e^x)^2?
yes
yeah
so it's what martin was saying earlier here
we already established that (e^x)^2 = e^(2x)
so if e^(x^2) = (e^x)^2 = e^(2x), then we would have that x^2 = 2x
ofc
do you see a problem with that result?
hm
yes
yes I do
wait
so I was solving for integrating factor
and p(x)=x^2-x
so it was e^ int(x^2-x)
and I was doing it
and I was like
e^x^2e^-x
so then
(e^x)^2e^-x
e^2xe^-x
e^(2x-x)
=e^x
can I assume that there are no parenthesis around the integral
because if I do, I get the right answer
(if I don't I need to do integration by parts I suppose)
Can some make help channel for me
Can u help me?
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Hello, I've been trying to solve this for a little while now (it's an extra credit assignment problem) and honestly I just keep running into walls. Could someone help me figure this out or show me how they might go about solving this?
Nevermind- I was overcomplicating it for myself and friend figured it out.
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Anybody have a good resource for learning integration?
At what level?
Enough for calc based physics
Typically you do Calc I before physics but Im doing Calc I while doing it so theres some stuff im supposed to know already
https://tutorial.math.lamar.edu these notes are pretty good if u work thru it
Welcome to my math notes site. Contained in this site are the notes (free and downloadable) that I use to teach Algebra, Calculus (I, II and III) as well as Differential Equations at Lamar University. The notes contain the usual topics that are taught in those courses as well as a few extra topics that I decided to include just because I wante...
The calculus section Ofc
Theyre my teachers notes. The issue is it doesnt really explain whats going on.
Do u want to understand the theory behind integration, or more what the integral represents?
the latter
It seems like it represents delta in some way
based on that
have no clue what happens with time though
Have u tried 3blue1browns video series on calculus?
It’s good for intuition and understanding
Probably best existing online explanation to get intuition
Should I learn derivatives first?
Yes
Integrals revolve around the idea of finding a function whose derivative is the function ur integrating
Derivative laws are easy and algorithmic
Integration is abt using those laws to undo them in some sense
Which is harder
Oh, wait I do know some derivative stuff. Only recently learned limits but I do know it now at least lmao.
Anyway, watching thru these videos will help with simply understanding what is ur doing by taking an integral
Tho questions are most important to be good at actually integrating, although slightly less emphasised if ur a physicist
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Line 3
When you subtract 2 log x from both sides
You already had -4logx there
You did minus 2 more
If you fix that you should get the correct answer
wdym? I didn't understand
I can't see the mistake