#help-26
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The component along P is some negative number. From the drawing I would say something between -0.3 and -0.5
sorry, -0.3 and -0.5
Which length is it represented by? Q?
In your drawing, you compare the length of Q to the length of P. The question is: How many times the length of P is the length of Q? half? one third? something like that. If it is half, then the component is -0.5
Ah i see
But what does this actually mean? I mean like if i say A and P are forces applied on an object placed at the origin then what does Q mean?
This is physics, not math. But the situation is more like this: Sometimes in physics, it is necessary to know the component of one force in a particular direction. For example with Lorentz force, you need to know the velocity component perpendicular to the magnetic field. So you take the velocity vector, and then take one component of it wrt. the vector perpendicular to the magnetic field.
Or you have a slope, and gravitation force, so the slope makes sure the object can only go along the slope. Then you look only at the component of the gravitation force along the slope, because the force perpendicular to the slope is swallowed by the slope.
So there are many situations in physics where this is needed
If you have multiple forces acting on an object and nothing else, you don't need components. You just have a total force which is the sum of all single forces
@unique tendon Has your question been resolved?
i shouldn't have brought in physics here.
But to sum up:
To find the component of a vector A along another vector B , all i need to do is find the length of the projection of A on B?
I think i have underatood what i needed to.
Thank you for your help.
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Hello , i need your help for Generalized integrals. i want to using comparison theorems determine the nature of
I have already done the part for ]0,1] it converge but i don't find for [1,+inf[
I have to compare with 1/t^2 so i try to reduce but i don't find
log(1 + u^2) > log(u^2)
This estimation makes the integral smaller, which is useful if we want to show divergence. But I'm pretty sure this integral converges. (and be computed with some trig substitution)
neat
IPB
it might be, haven't actually computed it
I don't understand why pi/2 + log(2). were it come from ?
oh log(1+x^2) < log(x^2 + x^2) for x > 1
you don't need to
my heuristic is that log(1+x^2) is basically 2log(x), and log(x) is slower than x, which means the quotient goes to 0 faster than 1/x, hence the integral exists.
you could just use this and then some log rules to show convergence on [1,inf)
exactly
or can i say ln(1+x^2) ~+inf ln(x^2) ?
=> ln(x^2)/x^2 ~+inf 1/x^2
=> so i prove with Riemann a > 1
Have I misunderstood your question?
I just need to find the nature of the integral using comparison theorems
Do you think this is enough for proving the convergence for [1,+inf[ ? @silent siren
not sure. probably, but I can't justify it.
maybe you need to show f(x) is continuous everywhere before you can integrate.
no, thinking about it, even if f(x) wasn't continuous, you could integrate it piecewise
in my school we can say it obious that f(x) on [1,+inf[ is continous and it is positive because devide two positive number (V x e [1,+inf[, ln(x) >= 0 )
Thank you for your help.
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So, I am working on part A and I was wondering where I should go from here?
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i need help
How can we help you?
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how can i simplify
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if ABCD is a square of unit lenght
perimeter of FEC = 2
Then find the relation between EC and FC
isn't fec just a triangle?
[redacted] obviously
language my friend...

by relation, you mean ratio?
ig just an eqauation containibng both the variables.
no not the ratio if you look at it
an eqauation
right
and is there any relation that you know for right angled triangle
pythagoras
FE^2 = EC ^ 2 + FC^2
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I don't know if you have enough information, is AF = AE?
then how are u supposed to find the angle
not given
maybe solve the equation u got from here
that will give you all line segments
then you find AF and AE (using pythagoras)
now u have all sides of triangle FAE
i tirired that
then use cosine law
ok
it might have something to do with the square instead of being a rectangle
maybe]
my teacher tloled me toi think outisde iof the box, literally
wait cosin law ain't allowed or something
containing trig
chapter - triangles
Without any further information, E is not a point but a locus
So is F
So the ratio is also literally a variable
You can see it wouldn't actually give any result
The angle is the cotangent. And without any information. It is just the cotangent
It's like saying x+y = z, find x,y,z
Unless I missed something in your original question
Does your question give any more information?
What does "square of unit length" mean
it means each side is of 1 unit
<@&268886789983436800> can you remove the helper role from me ??please .......
why
Go the id:customize and deselect "I'd like to help others"
Ok .thanks
I can't find it. there are only channels
click on the link
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Hi i have this equation and i know the differential are equal so i got to the 2nd equation (2nd image).
Now am supposed to express dy with only dx, x and n (without using any arcsin fnction) so idk what to do with the cos(y). I think there is a trig replacement i can t see idk
do you have any restrictions on y?
could possibly use pythagorean identity for sine and cosine
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How do I do this?
look at the third property
Have you learned properties of limits
he hasn't by the looks of it
he's a rookie
I’m confused by this specific one maybe I’m overthinking it
Do I plug the 5 to the x’s
Ohhh
6 times 8??
yes
Yep
And what do I look for the open or shaded circle?
How do I add graphs even
You add the y values??
They all have the open circle tho so it’s different y values
So DNE?
Halp🫠
<@&286206848099549185>
yes and add them for the first question
But which value is it?
There’s an open circle and a shaded circle
I don’t know what that means
I know the open one is like the limit like the discontinuity in the graph
And that the shaded circle is like a make up for it but I don’t know how it comes to be or which value is the real value
the open one
And at 0? How do I know what the value of the red graph is??
It can be 0.6,0.7,0.8 or anything
A limit only exists if the graph is approaching the same number from the left and the right. at x = 1, does the limit from the left = the limit from the right on the red graph?
No it’s two different values, so it’s DNE?
yep
You can calculate the slope of the blue one and once you figure out the limit as the blue graph approaches 0, you should see that you don't have to calculate the red graphs limit at x = 0
of the blue one?
Lim x—>0 means the limit is 0 right?
of the blue one yes
lim f(x) * lim g(x)
So what am I finding I don’t get it
What is the limit of f(x)?
They never gave me the function so I have no idea
They never gave me any numbers in this question
f(x) is the blue one
The limit is the open circle?
What is the limit of the blue one as x approaches 0?
0 I think
Why is there even a limit there if the graph functions normally
There is no hole there
Doesn’t limit means that it never reaches that number
Limits come in use later and its better to understand how they work now
Limit means what does the graph approach at some point x
Even if it can touch that point?
yes
So it’s 0 then right?
yes
So that means the answer is 0 cuz whatever the other answer is it’ll be multiplied by 0?
in all except one case yes, (if the red graph was DNE the answer would be DNE)
Oo that’s a good point
Thank you! That applies to num4 then and I’ll see if I know how to do 5
What’s the shaded in circle?
The "solution" y to the graph at that point x
So how can an open circle have a solution at that point if it’s DNE?
Yes, but for (f(x)/g(x)) lim g(x) = 0, then the answer is DNE
Open circle means that is not the solution y at that point x
I think you are confusing the two here, the f is 0
So it’s like 0 divided by something
I know, but I just wanted to point that out
Oh yes like if it was the opposite
I don’t get this still
yes
That’s like a hole in the graph
Meaning it doesn’t even exist cuz it’s impossible
So how can we still find a solution anyway for that point
Like in here why is it just a random dot at -1
The solution would be the circle/dot if one is given, if it just an open circle there. there is no solution at that point
that dot is the solution at that point
Yes but I’m trying to understand how to come up with that solution
Why is that the solution at that point?
Piecewise function
Why doesn’t the graph just go down to that point
What🥲😅
Why do we care about the non solution then and not the real solution
Shouldn’t we use the solution to calculate stuff
To show that limit x -> -1 f(x) =/= f(-1)
Not equal??
Aren’t we supposed to plug it there
Ohh cuz that’s where it wouldn’t be possible to solve
A limit is just what the graph approaches, it may not approach the solution at that point
So how do we calculate the shaded dot? And how is it possible for it to exist?
It is typically given
piecewise functions are basically a bunch of functions that are smashed into one over given intervals for each "sub-function"
They look like this
That looks like a tengant function is that the same thing?
Like tan(x)?
Yes like the tan function
no
Damn it
Hahaha
tan(x) = sin(x)/cos(x)
Ohh it’s like literally sin divided by cos that’s pretty cool
Like visually too
But isn’t it also pieces combined together
Since it breaks
Ohhh that makes sense actually
as sin grows bigger (up to 1), cos grows smaller (approaching 0), so larger/smaller = much larger
Thank you🥲 I understand this whole topic better now
No problem
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I want to know what I am doing wrong with this problem. My answer is incorrect and I would like to know what process would improve my thinking.
what precisely did you do
I just put 1/x^4
And the same thing with y after moving them to opposite sides of the equation
so y^-2 *y' = -5x^-4?
hmm
My 2nd step would have been $$x^4 : \dd y = -5y^2 : \dd x$$ from here you would just cross divide $-5y^2$ and $x^4$.
bacc
wait
is the point not to integrate by x once we get here?
like this?
Yes thats what I have
But the answer was still wrong
Maybe I made an error while integrating
sorry for the quality im having to do this in ms paint with a mouse
You should also first integrate both sides when you separated nicely
Oops
After this you should have $$\int \frac{1}{y^2} : \dd y = -5 \int \frac{1}{x^4} : \dd x$$
bacc
,rotate
Is there a command for flip
that should be x^3
Okay
since ur integrating x^-4
So now that I wrote that in I need to isolate y
tru, but ur basically already there
Now its just flipping the equation
yes but be cautious
well it's a little more inticate bc of the constant
put the C into the equation and then flip
,, -y = \frac{1}{\frac{5}{3x^3}+C}
so (-5 -3x^3*C)/(-3x^3)
hold on, where'd u get that from
applying (...)^-1 on both sides
but you've turned x^3 into x
oh I literally took it from here
doh
aint no way blud is doing integrals before linear equations 😭
Okay so how to I remove that 5/3 x^3 from the denominator
bacc
same logic
just take the lcm here
dr becomes 5+ 3x^3C
and nr becomes 3x^3
then cross multiply and solve
This might make more sense:
heiroglyphics ahhh numbers 😭
lmao jk
bro
but that's so slow

what? that's daft
Okay now I have this
and if u want to actually improve, making a machine do all of ur thinking for u is kinda antithetical to that
it's like sitting at one of those self-playing pianos and calling it practice
i'd leave it like that
and the nr is having dr as 1
I think that's the most elegant form
yup thats right
btw
why are u simplyinf that integration ans
C can be whatever tbf
just write +c to whatever u got
it does?
hmm then i guess u are okay
in that case absorb the 3 into it
But the professor never went into what can and cannot be absorbed into it
anything constant afaik
Okay
which doesn't inlcude the 5 here
u know what the +c represents right?
bc the C is next to an x^3
Yes it represents the integration constant
and what is that
So that 3 can be absorbed while the x^3 has to stay
ye
Still says its wrong
Maybe its a formatting error
Btw this is an achieve homework
wdtm?
That my teacher assigned last minute
maybe he wants the top three absorbed in too and it to be 5/3?
Oh shit I forgot the negative
Aight aslong as its the right answer I do not care
okay it was jus the negative I was forgetting
So anything thats directly multiplied or dividing the + C is absorbed?
Thats my last question before I go
it's kinda complicated
if it's within a fraction yes
but if you get e.g. f(x) + C + 5, you could absorb the 5 into C
Hmmm
So
What if I get like a situation like -(x+C)
Would the negative also be absorbed
ye that'd just become C - x
since you could've had -C earlier for ur integration const
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i dont get c
i chose a test value between 0 and sqrt10 - 1
when x = 2
f'>0
but when x = 1
f'<0
both are in the same interval
so im confused
which is which
,w differentiate (9-x^2) e^x
ohhh
btw im redoing
its because there's a - in front of the e^x
i didnt see that 😭
I didnt realize i pulled out a -e^x
ty
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super quick question if i do 420+3. is that 400 in sig figs?
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!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
@winter turtle Has your question been resolved?
no
Show your work, and if possible, explain where you are stuck.
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Can someone help me on four questions on my math homework? I want to understand the concept of domain and logs I have a test soon :(
Number 14,15,59,&61
for 14, the domain of an inverse function is the range of the original function
oh ok
i dont understand the steps to get that
i get confused when trying to find domain..
?
like so far I have root 1-x has to be greater than 0
yes
and x cant = 1
x can be 1
oh
sqrt(0) is 0
x cant be greater than 1 (x <= 1)
oh ok
so then i make a number line
testing the numbers between 0 and 1
wait
would it be [0,1]
?
oh so is [0,1] the domain?
im lost on how to ffind range..
do i plug in x and find y?
still no, try to think of when x is decreasing
yes
oh umm
you got x <= 1, x has to be atleast 1 for y to be minimal
so you find y for x = 1
and see how y changes as x decreases (if x increases 1 - x would be negative)
how do i find y for x,=1? plug in -1 into the equatio?
plug x = 1
yep
-inf,2
correct
yeah
g(f(x)) is g(5x^3 - x) , so g(4) implies 5x^3 - x = 4, solving that you would get g(f(x)) since it = x
but, for example if g(f(x)) = 4x, you'd have to solve for x and multiply that value by 4
so since g(fx) = x, in the f(x) equation, the x counts as the g(fx)=x?
litele confused
yeah, its the same variable
yeah
o wow
i might get some things wrong though im in g8
yeah
middleschoool
for 59 youd use that alogx = logx^a
yes
for which part
both terms
u r very intelligent
yep
then id do the other term instead
what about the second term?
there would be ln(sqrt(x)) as well
uh the term on the inside of ()?
and also notice how x^2 + 3x + 2 is factorizable
yes
sorry what do i do with that term the alogx=x^a?
oh ok
(x+1)(x+2) is in the ()
youd get ln x^1/2 which is ln(sqrt(x))
OH I SEe Tthat now
so far i hace : ln(x+2)+lnx-ln sqrt(x+1)(x+2)
can i get rid of the sqrt?
*the sqrt should be on the second term
so ln(x + 2) + ln(sqrt(x)) - ln(x + 1)(x + 2)
and by using logab = log a + log b
the last term becomes -(ln(x + 1) + ln(x + 2))
ln(x + 2) cancel
uh waiiit
?
i thought this supposed to be ln(x+2)+lnxsqrt? -ln(x+1)(x+2)
isnt there an x
no since the last term is squared
wdym?
oh so the x is jus sqrted?
yes
and do you see where to go from now?
is it js lnsqrtx + ln (x+1)
I SE
I SEE
I GOT IT
i accidently crossed out the minus sign lol
thank uu
i will attempy 61 on my own lol
fuck
you can make it (e^lnp)^1/2
so its p^1/2
yep
lnp would be cancelled already no?
so ln(p) is ln base e P and it turns into lnp/lne
no i meant this term
yep
so now its js log e
cuz it canceled out with the other ln p...
wait noo
did i do it wrong
ln e is 1
waiit i was right
ook
tyyyyyy
u actually stayed for all four problems LMAO thanks sm
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idk if its separable or not but i tried to separateto no avail so
possibly useful, the left hand side of the equation is d/dt of y^2
what u substitution do you mean?
u = y^2 + t might make your life a bit easier, I'd think 
it's fairly horrible without that transformation XD
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My brains having. Minor lapse in judgement and I’m sure this is some bs but I can’t figure out what’s wrong
jan Niku
whats the thought here
I could not tell you
Like I know it’s wrong but I’m forgetting how to do substitutions 💀
hmm 
first guess u(y) = y^2
but not quite
well, maybe
$u(y) = y^2 \to \dd u = 2yy'$
jan Niku
jan Niku
jan Niku
do we get cancellation
theres some weird domain restriction maybe
$y = \sqrt{v-t}$ so $\dv{y}{t} = \frac 12 \frac{v'-1}{\sqrt{v-t}}$
jan Niku
which gives the original ODE is
$2 \qty( \sqrt{v-t} )\qty( \frac 12 \frac{v'-1}{\sqrt{v-t}} ) = v^2$
jan Niku
which is $v'-1 = v^2$ 
jan Niku
i think this works
this is separable
youll need to back out y on the other end though
kind of a pain
Ty😭😭
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Is my equation setup correctly?
@peak edge Has your question been resolved?
<@&286206848099549185>
@peak edge there's at least one problem that I can see
The intersection looks like this
The integral you set up only covers between 1/4 and 1
You need to handle also the part where only x=y^2 is bounding the region
wdym
Can you solve it as the volume of parabola - the volume of conical cavity that forms?
And by the way how can you find the volume of parabola type graphs when they are rotated?
The green highlighted region are your bounds on x. I am too inept at desmos tonight to do the total bounds of the integral including the function, but you do the region between the two functions as you wanted.
But you leave out the area to the left of the highlighted region, which is still in the bounded area
So I need to find two volumes then
Yes, and add them together
.
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think about substituting t = 2x so that you can invoke the identity you sent
so what did you get
yes
which will differentiate to sec^2t/2
and 1/2
shit i need to sleep rn
😂
thnx
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for a) is it actually possible to know whether it's a positive or negative value? or do we just know it is ± 15?
ok, it is just a convention, and you probably use the right-hand rule like everyone else.
so with the right hand rule, v cross w would point down so it'd be negative?
yes
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why is p → q such an absolute mess to teach and to understand?
p = true
q = false
therefor if p then q is false
p = false
q = true
therefor if p then q is true
p = false
q = false
therefor if p then q is true
what is p and q used for again
can you give me an example, i remember using p and q for something, just dont remember what for
a proposition it can either be true or false, but not both at the same time
"if p then q"
If not p then you can't say it's wrong
Refusing this is refusing that things are false if and only if there's a counterexample to them
a stranger walks up to you and says "if pigs can fly, then ..." but you cut them off and say "hey there buddy, stop talking. i have already heard enough. what you are saying is true. discrete math says so.". you look up in the sky to see pigs flying. 🐷 🪽
then you start listening again
basically if you start with bullshit, it doesn't matter what you say after that, it's gonna be true no matter what
the thing that often confuses people is that implication is not logical implication
if true, then true = true
if true, then false = false
if false, then true = true
if false, then false = true
"A => B" is not "B can be proven by assuming A"
Surprisingly, it's not the definition
though there's a whole branch of logic about making it be
again, I go back to this question/statement
is it just that our brains are wired for conversational logic? talking like this in conversation doesn't make any sense.
we have to "unwire" our brains to truly understand discrete math logic?
the difference being that if pigs grew wings, it probably wouldn't change much about the world so you can't deduce much from it
But the implication is true because you don't have a counterexample
because we see implication as "provable from"
when in fact it's "there's no counterexample"
so you can have implications about things that are uncorrelated, and they happen to hold, although vacuously
But in general vacuous truths in math are kinda boring and a thing you just accept for the real stuff to work nice
so it's like hypothesis -> conclusion
if pigs can fly, then I will be an alien ... true
if pigs can fly, then I will be human ... true
well yeah
saying those are false is like making an assumption i guess?
since the assumption isnt true to begin with
the thing is classical logic includes "False implies anything"
Even "False implies anything and its contrary"
Because False being true implying a contradiction is not gonna break anything that wasn't already broken from False being True
saying they are true is making no assumption, it's just agreeing, this is bullshit to begin with
well you are saying if P is true, then Q is true, but if P isnt true then you cant make any claim about the conclusion Q, and this condition cant even be considered
i gotta smoke some weed to truly be open minded enough for this philosophical conversation
however it's proven that under classical logic, implication implies provability
But classical logic has the axiom (i.e. valid proof) "False implies anything" so deal with that
here's a way of thinking about it
suppose that false is true, we want to prove that P is true
well, P is either true or false
if it's true then we're done
if it's false, well, we know that false is true, so P is true
(another axiom of classical logic, not not A is A)
T→T = T you make a promise, you follow through with it. you win
T→F = F you make a promise, you don't follow through with it. you fail
F→T = T you don't make a promise, you follow through with it. you win
F→F = T you don't make a promise, you don't follow through with it. YOU WIN!
moral of the story: don't make promises, and don't follow through with them. you win.
no one can hold you accountable
No counterexample of you being untrustworthy
See, makes sense
discrete math is gonna turn me into such an asshole with this logic

making no promises of being helpful also means you aren't worth much as a friend
not according to discrete math:
p = being helpful
q = being a good friend
if p → q
F → F = T
I wouldn't try to attach a real-life connotation for →. Doing so would be missing the point that → is defined to work this way, and there's no need to justify it
"use less empathy"
I don't understand who might be hurt by this definition
the difference is math works with the concept of provability, which prevents quite the bullshit in practice
Vacuous truth might be weird, until you realize the opposite would be vacuous falsity, and that's also weird
Oh gawd, there's more stuff to learn on top of this already confusing concept?
`Trivial Proof: If we know q is true then p → q is true regardless of the truth value of p.
Vacuous Proof: If p is a conjunction of other hypotheses and we know one or more of these hypotheses is false, then p is false and so p → q is vacuously true regardless of the truth value of q.`
vacuous just means having or showing a lack of thought or intelligence; mindless.
trivial just means of little value or importance.
That's the line everybody finds weird. That F -> X = T
so we have proof that is of little value or importance.
and proof that is showing a lack of thought or intelligence; mindless

"If the moon is made of cheese, then I am made of cheese" is a true sentence
yeah
but so is this:
"if the moon is made of cheese, then i am currently talking to Kaynex on Discord"
or this:
"if the moon is made of cheese, then 1+1 = 2"
it's what lets "prove me wrong" be a counter-argument
If something is wrong there is a counterexample
and that's just fundamentally important as a property of our logical system
(while things having proofs is actually more complicated, because some dude named Gödel did too much shit with his brain)
but if you heard someone say this in conversation, I think there would definately be some red flags or confusion going on in the brain for the point they are trying to make
if the moon is made of cheese, then 1+1 = 2
they would just sound crazy
yes, but you don't
Because people put possible things after the if
if things may happen, then it must be that the conclusion may be true
Indeed, you're right. This throws a lot of people off.
You've got to choose either "true" or "false". You can't choose "doesn't make sense" since that's not an object in our logic.
Note that we already have a symbol where we choose false. It's ∧
more precisely
P(A) => Q(A) is one thing
P(A) => Q, where Q is not a function of A, means Q is true if there is at least one A for which P(A) is true
While with Q(A), you have flexibility
this is also a important fact to notice
LOL.. i don't know if I will ever agree with the logic, on a human/conversational level if the moon is made of cheese, then 1+1 = 2
but in discrete math I just have to memorize this: p -> q is only false when p is true and q is false. otherwise, it's always true.
maybe memorizing will help me a lot more here than "understanding"
yes it's the provability thing
hopefully the more I use it the more I will better appreciate it
it's that it's not
implication is weaker than provability
but we use the two interchangeably in math, unless you're explicitly working in logic
Tbh I don't often think about vacuous truth
i do find it interesting.. humans are so complex, interpretation of a statement can be WILDLY different from person to person
yet with computers it's just following very basic logic gates, and it's always always always the same result.. it is not open to interpretation on the weather of the day or environment it was raised in. at least not yet.
its most useful case is starting induction one step earlier than you should, and having a simpler case for it
(or weird edge cases in what you consider)
Most of the time we ever construct a p -> q we care about the case where p is true
yeah, it's easier when it's false, we just brush it off as bullshit
with true we must investigate further
if p is true, then q must also be true
to satisfy truth, or whatever it's called
"have equivilance" to truth?
Be true
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I need help understanding this question. I can get up to where it says "multiply E3 to (-1/4), but when I get to the add E2 to E3 part, I get stuck, why does E2 get to remain as is when added, while E3 is changed?
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reporting for duty
hello!
how old are you?
I'm 21
Yeah i can get up to the last part. Just confused why, when E2 added to E3, E2 still remained
I just need to know the reason for it being left unchanged
all equations isn't changed and just other equations are appeared!
do you understand?
Yeah, but when E2 and E3 were added together, shouldn't there be just one equation?
another equation is -4z=4
yes, there is a new equation after adding them together, but in the image, E2 still remained, alongside the new equation
My question was why, after adding them together, there still exists E2
when there are 3 variables, 3 equations must exist.
yes I undestand that concept
so E2 is still existed
so we just pick which one?
it is your choice
ok yeah this makes sense now thanks!
not at all!
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Split into two integrands
yeah but idk how to do the bounds
yeah basically you just want to get rid of the absolute value
so you want to split it into the section where the stuff inside is positive, and the section where the stuff inside is negative
(well, sections, in general there could be any number of them, but in this case it happens you only have to split it into two pieces)
so, for which x is x^2 - 1 > 0, and for which x is x^2 - 1 < 0?
Find y intercept. Then split the modulus into its 2 corresponding piecewise functions. And integrate between the y intercept and the extreme values either side
when x is -1 it equals 0 though
so what do i do there
^
x-intercept(s)*
ok
Ty long day ahah
so one of them is -2,-1 and the other is -1,0
$\int_{-2}^{-1}|x²-1|dx + \int_{-1}^0|x²-1|dx$

ok but its still absolute value
ye
so
but on the region (-2, -1) we know that |x²-1| is equal to x²-1
Now u gotta split the modulus into 2 different piecewise functions. One being negated the other just standard
how do we know that
well x^2 > 1, so x^2 - 1 > 0
and the absolute value of a positive number is just the same number, it's already positive so nothing changes
Easier way to think of it. Each time the modulus graph should cross the x axis. Instead the function gets negated and continues being positive. So it bounces and negates off of the x axis
im gonna be honest idk what ur saying
Well im down and out. Im too cooked to explain stuff lmao
oh so its when it equals greater than 0
for the bounds -1,0. -(x^2-1) is greater than 0
and for -2,-1 (x^2-1) greater than 0 or equal
right?
If ur curious i was trying to explain what u and the others were discussing but visually. So by thinking of the graph of the function. But yeah. That was it really
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is 100% 1 or 100 on a graph
1
so from (0,1) to (4,0) on a parabola would look like what
sorry I don't get what it would look like
is a horizontal stretch or compression
horizontal stretch
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Prove using induction that for every integer n >= 1 and real number x >= -1, that (1+x)^n >= 1 + nx
I am doing:
P(n, x): (1+x)^n >= 1 + nx
Basis step: P(1, -1): (1 - 1)^1 >= 1 + (1)(-1), thus 0 >= 0, base step is true
Inductive step, assume P(k, j) is true, then the inductive hypothesis (1+j)^k >= 1 + kj is true, then P(k + 1, j + 1) is true, that is to show (1 + (x+1))^(n+1) >= 1 + (n+1)(x+1)
then I am stuck, but i do see some people online to show to prove P(k+1, j) and P(k, j+1) separately. Or am i misreading the question that i in fact only need to prove k+1, and there is no need to show x >= -1 stands?
sorry
I was typing as you were typing
apologies for the ugly formatting, idk latex
Hey, I think it’s wrong that you are doing induction over n AND x. Because x is a real number, not a natural number
You can't use induction over all real numbers. You must be expected to induct over all n, but leave x to be free
In your notation:
P(n): For all x>= -1, it holds that (1+x)^n >= 1 + nx
oh damn, i am new to the topic
is it because real numbers are continuous? thats why we cant induct over it
Yea exactly. because even if you wrote down a correct proof and did induction over x, then you have proved the statement only for integer values of x, and not all the values of x in between
ah i see, that clear things up haha. i will leave this open while i try to write a proof
tysm
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^^
hybrid cars wont be driven any more in 8 years
that's right everyone will be driving monster trucks
the power line must start from the power station right?
yes
okay
I think smth like this
and since it is a line, its equation must be y = ax + b
yes
I know it by y=mx+c tho
we do!
do we?
we know c

