#help-42
1 messages · Page 17 of 1
What do you mean
its kind of like asking how to simplify a + b + c + d + e where a,b,c,d,e are just any numbers
,calc 1/24
Result:
0.041666666666667
Computers seem to handle that fine?
Well it has to be in will to optimize
Oh my bad, I thought of something different but never mind
Well let's say how would they handle
1 / 1000! ?
That's bad, I would assume
,w 1/1000!
Your question just needs to be scoped better. Solving numerical approximation is different from simplifying fractions
Ideally
It would be best to represent it as a factorial
Which is later on going to be multiplied by certain other factorial and scale it back
My friend and I are trying to make a certain algorithm work
And essentially that thing is part of the algorithm
It's optimization to an already existing thing as far as I Know
and I would have to do the coding part
This is an example expression:
-1/8! + 1/2! * 1/6! + -1/4! * -1/4! + 1/2! * 1/2! * -1/4! + 1/6! * 1/2! + 1/2! * -1/4! * 1/2! + -1/4! * 1/2! * 1/2! + 1/2! * 1/2! * 1/2! * 1/2! = 277/8064
This 277/8064 will be later on multiplied by some factorial
Which will scale it back
this is different to your original question, you didnt have products of factorials
Does that change anything significantly?
probably not, but it could have
what language? what algorithm? before we get too far down the xy rabbit hole
Any language I would assume, but I am trying to use Python since it's very useful for stuff like this
As for algorithm, I would have to keep that a secret for now :/
use sympy if you care about the result (but not the speed)
Speed would also be important, that's kind of the point of optimization
you cant have both if the problem that you've proposed is optimal ¯_(ツ)_/¯
XD
Thanks for the tip tho, I will take a look at it
But, can we anyhow simplify this mathematically
Mathway has successfully expressed this thing as that fraction up there
like the usual way you add fractions
Are you really sure that will ... work optimally xD?
you are asking whether you can simplify it mathematically
To phrase it mathematically, do you think that's simplified enough?
how more would you simplify it than as one fraction?
But to get to that one fraction maybe you will have to calc 1000!
And that's not very great
I am trying to evade that
which brings me back to the original point of this being way too general. you can't hope for a general simplifcation that's going to work no matter what expression you give
simplifications that will avoid big calculations will be a result of cancelations because of the specific terms in an expression
like how 24/6 = 4, but being able to do that simplification was completely dependent on the numbers being 24 and 6
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Hi everyone, I hope you all are doing well today!
I am working on a creating some parametric gear drawings by means of code and for that need to use an involute curve.
Calculating the positions is no issue, but finding out where to start an stop is an issue.
To this end I have identified this formula to find out where a given angle would create a point on the involute curve:
involute_position = angle - atan(angle)
Now I am looking for doing the inverse to find out where I should start/stop.
The question would be:
Given the involute position (an angle) how would I find (or approximate) the input angle?
,w x = y +arctan(y)
can you give an example?
Of course! Let me draw it up real quick
are you just trying to solve equations that look like 3 = theta + atan(theta)?
I hope this illustrates the question:
No, I am looking to approximate theta in the equation 3 = theta - atan(theta) when given the value of 3
what's the difference between that and what I said
My mathematical vocabulary isn't too great, so it might be the same.
Ah, I'm looking for theta - atan(theta) instead of theta + atan(theta) I'm not sure if there's a difference?
oh yeah my bad typoed that
so you want to solve something that looks like c = theta - atan(theta)
like do you just want numbers for practical purposes or are you looking for a proper analytical solution
Do you have the tools to calculate theta - atan(theta) given theta? You could use derivative then to aproximate
It would be numbers for practical purposes
practical purposes, you can probably just ask wolframalpha
,w solve 3 = theta - atan(theta)
if you need to write it in code, you can use some numerical optimization methods
Ah I see, so that would provide individual values
As 3 would be a dynamic value, I think the analytical solution is probably what I'm looking for then?
are you writing code for it
Yes
okay then you can use a numerical method
in this case, there are a few ways to do it
one way might be to rearrange the equation to theta = c + atan(theta)
and then solving this amounts to finding a fixed point
I see, so I would swap out the function, and then iteratively find the closer value?
well, hmm idk if that would work so well, since the derivative at the root is 1
you could certainly use something like Newton's method
there are plenty of root-finding algorithms
at the worst, bisection would probably do the trick
in particular, the equation you're solving is really well-behaved; it's monotone nondecreasing
That makes sense, I'll try that out!
so even a simple binary search is guaranteed to converge
Thank you, I will try those methods out!
Bisection can ensure decimal places
So if I understand correctly, there's no direct method for inverting this formula, and as such, using some root-finding method is necessary to approximate the values?
Thank you for your help @teal coral and @somber finch!
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Need help
whats the nature of ABCD ?
Parallelogram
@sullen heart Has your question been resolved?
is there a way to prove that AM is the bisector of BAC ?
Possible if AB:AC = 2:3
im looking for another but i cant seem to find one
Might be possible with constructing a line
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Need help
well I do have an idea
@sullen heart Has your question been resolved?
enlighten us
Yes please
nvm it didn't work 

my idea ended up with a conclusion that 5=3qsrt2 
???!!????!!? What does that mean
@sullen heart Has your question been resolved?
<@&286206848099549185>
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I need a hint for how to handle the exponents here
Could I multiply by something to make the math smoother?
@sudden nebula Has your question been resolved?
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Good Evening!
Can someone help me to find the approach they used to get that result?
I know that the first fraction is 2 but what about the rest?
looks like ratio test
I am aware of the criteria, I just dont udnerstand how they transformed the first equation to the second
well presumably plugged in a_k+1 and a_k
And from theory?
.
Because 2^k+1 /2^k is 2
(k+1)! = (k+1) * k!, the k! cancel and you are left with (k+1) in the numerator
then squared
and (2(k+1))! = (2k+2)! = (2k+2)(2k+1)*(2k)! and the (2k)! cancel
and you are left with (2k+2)(2k+1) in the denominator
What is this (2k+2)! = (2k+2)(2k+1)*(2k)!
well factorial
(2k+2)! is the product of all numbers <= 2k+2
(2k+2)(2k+1)(2k)(2k-1)(2k-2)....3*2*1
but that second part is just (2k)!
what did you think factorial was
I mean I get the concept for natural numbers
But not in such a way
Thats actually great help!
Appreciate it 👍
youre welcome
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If S is normally distributed with mean 1800 and variance 317.4
and L is also normally distributed with the same mean and variance
how can u work out the probability that S is atleast 25 units larger than L
textbook has the answer but no workings lol
<@&286206848099549185>
Very carefully 
thx
use z score
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Um hello can I please just have some help??
Please don't occupy multiple help channels.
sorry
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log_10(1/sqrt1000)
how do u simplify this
what is the square root of 1000?
in a more simplified form
well okay
ik its around 31
1000 is just 100 times 10 right?
yea
right so what is the square root of 100
10
10^3
10sqrt10?
yep
now,
mhm
can you write sqrt(10) in exponential form
do you know anything in particular we can do with this?
3/2
3sqrt10
no
oh wait
where did that come from
3/sqrt10
1+1/2
you said bases dont change at all
3/2
we are only dealing with exponents
you have [
\log_{10}\parens{\f{1}{\s{1000}}} = \log_{10}\parens{\f{1}{10\s{10}}} = \log_{10}\parens{\f{1}{10^{\f32}}}
]
yea
i think it is best if you try to continue this on your own
because i dont want to simply hand the answer to you
you wouldn't be learning anything in that process
why not try and attempt to continue it?
walk me through it
im understanding
or
what if i continue and u see if itts correct
no
no like apply the exponent law of $\f{1}{a^n} = a^{-n}$
yeah what u were already doing
yea
so what do u have now
-1
ye
wasnt hard
now i got one more question
log_1/9(x)=-1/2
i simplfied it to
log_3^-2(x)=2^-1
idk what to do after
@remote mural
last ping i promise
lol
anyone?
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$x_i \geq 0$
Ann
2+s-t >= 0, and -4+7s-19t >= 0, and so on...
ok
ight got them
what now?
now graph them
that's what i would have done
it is not yet immediate just from looking at these ineqs that the five halfplanes they describe actually intersect in one single point
@drifting vortex Has your question been resolved?
i got this
with the credit of chartbit the goat
it says there
t = 0
💀
oh, right. yeah.
another Ann L
🙄
might have to change from rare Ann L to common Ann L
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could i get a hint?
i dont even know where to start
maybe use a five digit variable abcde
and when you cross one out and add
you can create a system of equations
@karmic ridge Has your question been resolved?
so five different equations
??
abcde+bcde=41751 for instance
how do i solve this
it looks liek that doesnt work
because e + e cannot end in a 1
so try crossing out a different one
that's the answer then
you can;t not cross e
so you must cross e unles that doesn;t work either
must be 1 or 0
only one equation
got it?
why?
is e is an odd number
e + e will always end in an even number
the only way you can end in an odd number is by adding an even and odd together
1+1 = 2
3+3 = 6
5+5 = 10
now?
i understand
how did you get that
our equation is
11000a+1100b+110c+11d+e = 41751
e must be such that 41751−e is divisible by 11
i checked all options to find that e=6 makes it divisible by 11
that was pretty dumb of me
like the remainder of division bt 11 would give me 6 directly
at least it worked
now since 11000a+1100b+110c+11d = 41745 we can tell that d is 5, other letters don't even contribute to the last digit
wait how
it's a number that you have to subtract to make something divisble
it only gives one number, smallest, so if it was appropriate e could also be 17 and 28 etc.
but it's only 6 thaat can be a digit
pardon...
how did you get 17 and 28....
well they cant be anything
right?
but we still have to find the possible digits?
we have to find the possible values of a, b and c?
what would be the solution for this? 11000a+1100b=41591
40700
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I need help understanding how to solve nested quantifiers
@wary condor Has your question been resolved?
@wary condor Has your question been resolved?
<@&286206848099549185>
I don't have a frame of reference on how to solve this
so far I've only been given statements to negate
is it X is even --> x^2 + 1 is even?
idk if my train of thought is correct cause im struggling to find anything online that is similar to the questions im being asked.
But, for negating the statement do I negate everything
or just the 2nd stuff
so would it become
x ≥ −3 −→ x^2 < 9
and false
how much DO you know about this? because I can walk you through it a little bit (i think, it's been a while)
This one is phrased as an "if, then" if i'm understanding it correctly, so we flip the quantifier ("for all" gets replaced with "there exists an x" ∃). and then we say x is even AND x^2 + 1 is not odd (can just say even)
that's what i'm using to kinda refresh my brain on it
remember that push comes to shove use a truth table
@wary condor Has your question been resolved?
hey sorry, I'm absolutely fried rn i'll have to get back to this tomorrow ty for the link it looks like it has a lot of useful stuff for me
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no worries, here's another one that I found for what it's worth
https://www.ccs.neu.edu/home/lieber/courses/algorithms/general/quantifiers.pdf
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This is the question I have an issue with.
This is what I have so far.
I understand I need to derive q to get i, but the software is saying my q is wrong.
The lecture on this section was very rushed in that it didn't explain any of the numbers, it just gave the initial top equation with values, then the next line was the q and i, without showing any of the steps in between.
@frosty mica Has your question been resolved?
Hmmm, that integrating factor is looking a bit 
QC = V on a capacitor, is it not?
nvm I'm an idiot
Q = CV
but yeah your differential equation looks wrong, because q(0) = 0 is one of the boundary conditions
Also seems like you implies that $\frac{1}{5\times 10^{-6}} = 5\times 10^{6}$ on that first line actually
@upper sparrow
should look something like q(t) = k(1-e^(-t/RC)) iirc
I'm not entirely sure, this entire section was not really explained whatsoever.
It's an online class so the teacher just assumes you know everything they don't explain, which I don't.
Where does it say that?
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This is what I'm stuck on
This is what I have tried
I'm just trying to wrap my head around all of the different variables/constants because the book is so egregiously awful at explaining it, that it doesn't seem to actually explain it, in my mind.
I understand that K is the limiting capacity, but r is just described as f(0), but I have no idea what f(t) represents.
what do you mean by K and r
It's what's given in the book\
The book doesn't really explain anything clear enough for me to understand
K = carrying capacity, r is a constant where f(0) = r
f(P) =(r-rP/k)
It would seem so, yes.
it seems like rP/K is just a fudge factor to delete some offspring
I am assuming N and P are interchangeable here
For the purposes of the answer to the question
not interchangeable, just different names for the same thing
Yeah
the question doesn't talk about P
Yeah
I'm just extremely confused because this section is so poorly explained
I'm mainly confused on the N(0) = and the N(1) =
How do I tie those into the original equation to find r?
Or are those values for c?
wait so are you confused where the form of the logistic equation comes from
or are you confused about how to actually solve the problem
Essentially, yes.
Both?
I don't really know where to find resources on this, since I haven't been in college in 5 years.
I am quite out of the loop.
I dunno if it's that important for passing to know where the equation comes from
but as for actually solving the problem, you just need to know what the general form of the logistic equation looks like
I would assume that dN/dt = N(r-rN/K). Do I need to integrate that to get N(t)?
and then find the constants like you would any other function
this is a differential equation
you need to solve it to get N(t)
you see that there's a derivative of N on the left side and the actual N on the right side
so you can't just integrate
solve it like you would any other initial value problem
Separate it for N on one side, t on other?
Would it have to be a Bernoulli equation since N is a denominator?
Oh never mind
I forgot you can integrate like that
Kinda like this, but if I integrated correctly?
Somethin more like that I think
Am I not supposed to have a P^2? The book is saying I'm wrong.
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?
?
?
they factored the denominator
how
kheerii
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Huh
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how can u tell when certain letters are reffering to certain meanings
im starting to notice letters being used for multiple definitions
can you only tell based on the other letters around it?
Normally you only know that a letter means anything if the problem tells you what it means
I could give you a question and say, "let x = the number of rubber ducks" or a different question and say, "let x = the number of cars"
and the only reason you know what "x" means is because I told you what it means for that specific question
Letters start to get used a lot for the same things and there will be patterns, so if sometimes you don't get an explicit explanation but you recognize what the letter probably means, it might be safe to guess.
hmmm ok thank you
so the letters that DO change are called variables correct?
and the ones that do not are Constants?
"variable" and "constant" are not attributes assigned to letter, just to quantities themselves
i.e. there are not letters that are constants and letters that are variables
but in a specific setup, you can choose to represent variables and constants by whatever letters you choose
e.g. the speed of light in a vacuum is constant and we usually use the letter c for that
but that does not mean c is always representing a constant value
yes and you can have an equation like this
AustinU
where a, b, and c are "constants" but x is a variable
although they are all letters
so it is entirely context-dependent, just like the definition of what the letters themselves signify
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the one with the truss
What's a truss
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is the null space of a matrix just the # of free variables?
the dimension of the null space can be thought of as the # of free variables
I believe
and then the col / row space dimensions are just the # of pivotal columns
which is also the rank
right?
... wait a sec
Yes
that's not how I was taught it but that works fine, yea...
thank god im not in medical school lmao
LOL wym
i would probably explode with the amount of memorization i'd have to do
i hope i wont have to use this later
linear algebra can be useful
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if you have an operator that acts on f(x), what is the significance of a '^' above an x in its definition (like in the example below)
ive seen operators where if the goal was O(f(x) = x * alpha * f(x) they would write the x without the hat on top
so i'm confused as to why i'm seeing x hats in operators and if they mean something specific
@glacial elk Has your question been resolved?
@glacial elk Has your question been resolved?
@glacial elk Has your question been resolved?
do you have more context?
i'm trying to understand notation so that i can do a question for a piece of coursework
(which is testing linearity of operators)
i dont really think i understand the topic enough to phrase it in a way that makes more sense
i guess since i'm unsure of how vague the term 'operator' even really is
this is for example the hamiltonian operator [using the same field/definition of 'operator' i am studying and attempting to understand]
but i'm referring to any operator O that has notation 'x^' within it
@glacial elk Has your question been resolved?
@glacial elk Has your question been resolved?
operators in quantum mechanics are just given a hat on top to show that they are operators. in the example of the position operator $\hat{x}$ we just have that this operator just happens to be the position, $x$, so $\hat{x}=x$. a different operator like momentum is not just defined as the "momentum" (whatever that would be in quantum mechanics since velocity is not well defined) but as $$\hat{p}=-i\hbar\pdv{x}$$ or more generally $$\hat{p}=-i\hbar\nabla$$
Duh Hello
so in this case $\hat{O}$ is just multiplying some function $f(x)$ by $\hat{x}\cdot\alpha$ (from the left). since $\hat{x}=x$ then this operator is just regular multiplication. so this O operator is just scaling a function by a factor $x\alpha$
Duh Hello
to test for a linear operator you just need to check if this holds where $\alpha, \beta$ are scalars, $A$ is the operator and $x,y$ are the functions, vectors or tensors etc.
Duh Hello
@glacial elk Has your question been resolved?
No, we do not encourage people to use chatgpt thanks. Read the rules.
I believe this is dependent on context - given none, I'd guess unit vector perhaps???
I'd probably advise asking in the relevant topic-specific channel
its quantum mechanics, $\hat{x}\equiv x$
Duh Hello
unless they just threw in the qm hamiltonian for no reason
Sorry, wasn't here for your answer, this explains it perfectly thanks 👍
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What do you want help with?
this
Which part? Where are you stuck? What have you tried?
@fresh mountain Has your question been resolved?
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anyone knows how I get from left to right?
@turbid osprey Has your question been resolved?
Find eigenvalues and eigenvectors of the matrix
why is it allowed to say that it is x1 and x2 on the underlined red line ?
Follows from matrix multiplication rules
oh wait did he just multiplied it?
so he made it row echelon form and multiplied it by that [x1, x2] at first step right?
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Hello, I’m practicing some logic questions in preparation for a competition in March. One of these questions is the following:
You can see in the figure the sides of the rhombus divided into four equal parts and, inscribed inside the rhombus, the dark rectangle. What is the ratio (expressed as a decimal number) between the area of the rectangle and that of the rhombus?
well i'd start trying to compute the small side of the rectangle
considering the soze of the rhombus is one
each equal parti is 1/4
using pythagoras
that rectangle's small side is 1/sqrt(8)
hm
I’m trying to set up an equation starting from the triangles next to the rectangls
you'r correct
we now for sure that the triangle is isoscele
Yeah
oh wait
imagine
deleting that rectangle
from the total area
is it possible to compute the new area ?
Calling x every fourth part of the side of the rhombus, and α the vertex angle of the small triangle next to the rectangle, the total area of the rhombus is as follows:
indeed, I precisely calculated the total WHITE area
I think I got the result!
I checked and it’s correct, thank you guys!
The other question I need help with is this:
Number 2020 admits 12 divisors. If you write them in ascending order, the seventh is a prime number. What other year of the twenty-first century will in the future admit twelve divisors with the same property (if they are ordered in ascending order, the seventh is a prime number)? Can you name at least two?
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ChatGPT seems to have called out an issue with this equation's units not actually equal to m^3/s. I am confused because it seems to actually be right. There is a left over 1/2 of this portion of the equation, so that means it has to be higher than m^3?
nah the units do seem to be
chatgpt says that sqrt(9.8m/s^2) has units of m/s, but it has units of sqrt(m)/s
Interesting so the square root of units has its own rules you have to learn as well?
Don't use chatgpt for math
what rules
sqrt(m/s^2) is just the rules for fractions
chatgpt the best for math
Gotcha
This makes sense now thank you guys for your help I guess chatGPT can’t help with everything
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could someone please look through my solution to verifty it? no answers were posted for this set ):
nvm can just use chatgpt!
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can you define dividend?
what piece of the problem are we looking for
thats where id start
,w dividend
jan Niku
and we're given quotient and divisor
what can we do
the remainder contains the divisor
think of how you write them
are you sure it was simplified?

its not simplified
try it yourself
youll get your answer
no
think about what the quotient and the divisor are here
we know the structure of the remainder gives us the divisor
which part is the quotient
and the remainder
okay
now if dividend/divisor = quotient
give me a formula for dividend
yup
so we know quotient, its that whole thing plus remainder
and divisor is x-3
its $(x-3)\qty( 2x^2 + 7x + 21 + \frac{67}{x-3})$
jan Niku
jan Niku
OH
haha
well it just cancels the fraction right
$(x-3)\frac{67}{x-3} = 67$
jan Niku
youre asking how we have a +4
since we know we have a +67 floating around from the remainder
that means were hunting for a -63
can you see where we might pick this up?
where do we have just a number times just a number, with no x's
yup
so getting +4 makes sense
np
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Hello, so I'm in 9th grade and I was just revewing my teacher's correction of a test that didn't count until I saw that she multiplied the numerator and denominator by four on the red circled part.
I'd like to know why she mutiplied it by four.
I'm pretty sure she explained why during class but I forgot what she said 💀
To get a common denominator to add the fractions
Ohhhh I'm so stupid
It's because of the other fraction's denominator correct?
Yes
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How do i do solve b?
its where the function starts repeating
so from here to here?
note that you cannot include the point where it has repeated
yeah
no idea, seems weird
in that case wouldnt it be 6
when we reach the first bottom tide
cuz we only want one y value associated to one x
so if we go back up to the 2nd high tide we use the same y-values
where these lines are
@warped rampart
yeah ur right, mb was thinking about it wrong
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so i have a quadratic formula worksheet here and i know how to do it most but i have to break down the 60, i broke it down into 10 and 6, then 3 and 2 (for the 6) then 5 and 2 for the 10, but i forgot how what to do next
you are trying to simplify the square root right?
oh wait, you did the formula wrong
i did?
what’s that
square root*
6 squared it’s 36
yep
yah, you did the formula right, but the math is wrong
a is 1, b is 6, c is -7
you have this equation right? $\frac{-6\pm\sqrt{36-4\left(1\right)\left(-7\right)}}{2}$
Judgemental Snail
yeah
we can first multiply 1 and -7
getting this
$\frac{-6\pm\sqrt{36-4\left(-7\right)}}{2}$
Judgemental Snail
oh i didn’t know that
ah ok, redo it then i can check your answer
thanks
np 🙂
@exotic bone so i broke 64 down
you dont need to do that
64 is a perfect square
meaning you can evaluate the square root and get a whole number
ohhh i see
what number would you get if you do so?
1 right?
no
or 8
yeah but don’t you simplify that to 8/8 and then 1/1?
taking a square root is asking yourself, what number, times itself results in the number in the root
so in this case, what number, times itself results in 64
8 times itself
yeah i know square roots but i forgot what to do next
well we can replace sqrt(64) with 8 because sqrt(64)=8
$\frac{-6\pm\sqrt{64}}{2}\to\frac{-6\pm8}{2}$
Judgemental Snail
yep
and then just one last question
whats the question?
for this do i do -12 on both sides to make the other side equal to 0
yep, did you get your answer for this though?
that way i can label A B and C and use it for the quadratic formula
i have to do it out but yeah i will get the answer once i do it out
k
np, but yeah you will subtract both sides by 12
and to get approximate answers how do i do it on a ti84
the teacher taught us on a ti83 how to get what x is approx. but doing the same doesn’t work on my ti84
she showed me i have to do it differently but i’m not sure how
i tried that with another one but it said non real answers
for which one?
k
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$\int_0^1 f(x) x^n dx = 0$ Prove that $f(x) = 0$ on [0,1]
please request a new nickname
and n is some positive integer
@muted marlin Has your question been resolved?
@muted marlin Has your question been resolved?
presumably this has to be true for all positive integers n?
it's easy to find counterexamples if it's only true for one n
yeah for all n
proof by contradiction seems viable, suppose f(x) > 0 at some point
find a polynomial which has no roots in [x-epsilon, x+epsilon]
and hence has the same sign throughout [x-epsilon, x+epsilon]
but wouldnt you lose generality if you suppose f is some polynomial
would it help if i mentioned that we're learning sequences of functions
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Can someone help me with the circled question
Using this formula:
Just compute it I think
According to my mental math, y is chosen for integral to give a nice perfect square to remove the square root
I would find derivative of the function first. I’d get this, right?
And then I’d evaluate from there?
Yes
I’m not good here…would I foil what’s in the paranthesis?
Like this?
You're not telling me you're trying to find the length of a curve through integration yet need to be hand-held to expand a square
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I think I have created a "new" type of best fit plot for an asymptotic data set (think something like a box office graph), and I want to know how to improve it. I found an approximate slope at each point by taking the average slope of the two surrounding points, then entered this data into an exponential best fit calculator. Then, I wrote a function that took an integral of this best fit exponential curve, which gave me a best fit line for the data set. What are the flaws with this approach?
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Hi I'm trying to compute this integral, I need to do it by substitution to "show it"
I attempted first to sub u=x-5, and then from there u=3 sinh t
But I don't believe the answer should have logs, as I believe the integral of sech would have, it should come out as arctan I belive, anyway, any help would be amazing! Thanks
the anti-derivative of this is just something with arctan(u)
Ik by recognition it’s 1/3 arctan (u/3) but I have to show it by substitution I believe
then do u = tan(t)
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do I need brackets on this part that I circled after taking the derivative?
yes
ty
but also you're doing this the long way
write f(x) as a sum of terms and distribute the derivative to each term and you'll only need to use power rule
this is the Chain Rule?
pwer
Oh OK
you can split the fraction into 3 separate terms
d/dx (4/x) =?
is this always the case for taking derivatives? good practice to keep them in brackets even after you derive? or not always