#help-0
1 messages · Page 548 of 1
mb, I looked at the wrong domain
Why have you taken the absolute value for the second integral
Huh?
$\int_0^{\pi/4} \cos\left(x + \frac{\pi}{4}\right) - \int_{\pi/4}^\pi \cos\left(x + \frac{\pi}{4}\right)$
Roenbaeck
If you take the absolute value then you don't need to subtract them
Wait why subtract
That's what I don't get
To reverse the sign.
Shouldnt you add the two areas?
The integral for the area below the x-axis will be negative.
yw
Handwriting too good
Latex question. How can i get this aligned correctly?
\begin{align*}
F_{\triangle MAB}&\leq F_{\text{Sektor}MAB}&\leq F_{\triangle MAC}\\
\iff\frac{\sin{x}}{2}&\leq\frac{x}{2}&\leq\frac{\tan{x}}{2}
\end{align*}
LYNIX
what are domain and range by definition?
Doman are the x values range are the y values
,,
\begin{alignat*}{3}
F_{\triangle MAB}&\leq F_{\text{Sektor}MAB}&&\leq F_{\triangle MAC}\\
\iff\frac{\sin{x}}{2}&\leq\frac{x}{2}&&\leq\frac{\tan{x}}{2}
\end{alignat*}
@ripe bough ^
yes, so what x values (horizontal axis values) can the graph take on?
@rich basin thanks. What exactly is alignat and what does the 3 mean?
Roenbaeck
The extra 3 shouldn't have been there 🙂
alignat tells latex how many "columns" you have, and makes the output more "compact"
I don't understand that
where does the function start and end horizontally?
nice thanks
Starts at 1950 and ends at 2000
so what's the domain?
@rich basin Is there a way to write the calculation | * 2/sinx a bit nicer? i just used a lot of spaces and |
Hmm... you could have an additional column and let it be empty on the other rows?
You need the extra & at the end of every row though, to indicate that empty column.
\begin{alignat*}{4}
F_{\triangle MAB}&\leq F_{\text{Sektor}MAB}&&\leq F_{\triangle MAC}&&&\\
\iff\frac{\sin{x}}{2}&\leq\frac{x}{2}&&\leq\frac{\tan{x}}{2} &&&|\cdot\frac{2}{\sin{x}}\\
\iff 1&\leq\frac{x}{\sin{x}}&&\leq\frac{1}{\cos{x}} &&&\\
\iff 1&\geq\frac{\sin{x}}{x}&&\geq\cos{x}&&&
\end{alignat*}
LYNIX
@glass lichen -0.5 and 0.4 I think
no
the allowed horizontal values are from 1950 to 2000. Domain is the set of allowed horizontal values
so what's the domain?
-0.5 and -0.1 I think or idk
what are the x values allowed?
no clue why you keep saying decimals when you already told me the horizontal values are 1950 to 2000
Hello
I'm trying to evaluate this integral
Using the definition of the integral
I got it wrong tho
Its supposed to be a/3
And I got a/6
Why?
,w sum i^2 from i = 1 to i = n
Ok so I’m learning trig rn or something and I get how to put it in the calculator but what I don’t get is if I use sin cos or tan
Like when I use it
Can someone plz explain to me
Is there any way to find arc length (ds) in any given co-ordinate system using Jacobian?
($ds=\sqrt{{dx^2}+{dy^2}}$)
I can find in Cartesian, polar,cylindrical and spherical but how to find it in any given coordinate system?
Riyango
anyone knows add maths its geometry btw 😪 been stuck on the question
i only could find the gradient 🥲
,rotate
which question...?
8a 💀
<@&286206848099549185>
sorry for the ping but ^
ok so can someone teach me the entire 11th syllabus of indian mathematics?
💀
i have an exam in a few days
@trim hull We do not help with test questions.
its not a test
all u had to do was not take a full screen shot man
lol
Can anybody help right now.
ye we cannot help with exams/quizzes
rules and all
do you know logarithm rules?
uhm, are you allowed calculators?
Yeah
put that on the calc to get x
one min lemme send you a pic
Bruhhhhhh
yeah?
But it does say use special properties
ohhh well then now lemme think
ayt
@slow scaffold i got it
sending
A*
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
@slow scaffold there
Okay
you know that rule?
I think so
well if you see i took ln on both sides which is the same as log 10
Okay
so i made no difference to the equation
then just applied the power property and took the x down
from where you probably know it
Yeah it is
np
Are you familiar enough with trigonometry? Like do you know what sine is?
If so, we don't need to consider 3 cases. We can do this pretty nicely
Let me know when you're here
Bob Ross pfp good
$V_{\triangle\text{Prism}}=\frac{1}{4}h\sqrt{-a^4+2\left(ab\right)^2+2\left(ac\right)^2-b^4+2\left(bc\right)^2-c^4}$
Tasmav
The base area is 1/2 * 12.8 * 4.8, then multiply it by the height. The volume then is 344.064.
Is this channel open
I believe so
I mean.. my guess is no since C isnt a midpoint?
ok
How are we supposed to find c
You can find the center of parallelogram (as a midpoint of DB). Note that it is the point where diagonals intersect so it is also a midpoint of AC.
slope of AB is the same as slope of DC
Ohhhh you are saying that the midpoint of db is also for ac?
Exactly
Ohhhhh thank you so much
hi any channels not in use?
We could go #prealg-and-algebra , if it fits, @alpine sable
Sure, let's go prealg
Is it same for rectangle btw
because rectangle is a special case of parallelogram
Does find the sum mean simplify or factor
I have another issue
need more context
Can i quickly ask
What would I do
collect like terms
yes
yes
Ok ty
k and y are obvious, then the slope for OA is the same as the slope for CB
anyone know bigO notation for computer science
Example 1
Use the given triangle to fill in each blank.
sin B= __
tan B= __
__ B=ac
__ A=bc
ok
what's this for
Where the questions
what's the definition of sin(B)?
what ratio?
do you know the ratios?
ahh its fine i dont even know what im asking but ty anywayyy
@alpine sable here
Here
so first we have to do $\log_{25}9$ right
αρη
Um, yes but am I supposed to react to an emote?
no
Oh okay. Yes.
and we know $\log_{25} 9 = \frac{\log_{10} 9}{\log_{10} 25}.$ right
Yes
αρη
αρη
Ok
so do that with a calcualtro
On it
3.4130309724?
Er, it's wrong?
@alpine sable
I'll try with a dif calculator if you would wait a sec
sure
send a picture of your calculator
i tried it on my calculator, wolfrom alpha, and google calculator
i got 3 everywhere
Maybe I'm entering the equation incorrectly
send me a picture of what you have on your calculator
its 5 raised to the power of log9/log25
Ah
you did 5 multiplied by log9/log25
try doing 5 to the power of log9/log25
Got it!
Yes
An 8 meter long ladder is erected up a wall. The distance along the ground to the wall is 3 meters.
How high up on the wall does the ladder reach?
At the same time, the same ladder reaches 6.5 meters up the wall.
Calculate the angle that the ladder forms with the ground.
oh thought u guys were done, sorry
now we have to do $3^(log_3 2)$
αρη
On it
so $log_3 2 = \frac{log_2}{log_3}.$
αρη
Yes
so $3^(log_3 2) = 3^( \frac{log_2}{log_3})$
αρη
understand?
Yes
Yes!
Great! Do you have any more questions?
Or do you need help with anything else
Not right now, I'll do similar questions then move up to next type of questions
Sure, feel free to ask me any questions if you have any difficulty with the other types of questions.

Thank you! You helped me a lot!
No problem !
Thunder7
Thunder7
can someone explain how u can easily get the two numbers that will add and multipy?
cuz i honestly cant just guess the numbers im slow
Let b=-2-a, substitute in the a*b=-35 to get a quadratic in a, solve for a
so it would be b=-2-a*b=-35 ?
Sorry, could you clarify?
you said plug a*b=-35 in b=-2-a in a
You can do a*(-2-a)=-35, or -35/a=-2-a,
M, N, P being aligned means vector MN+ vector NP=vector MP. And keep in mind that AB + BC=AC. Hope this helps
it also means that they are a 180 angle
ye
I mean if I do won't it become
,,a(ax - a - 4) -3(ax - 7)
Thunder7
I just can't do anything with it
how do i calculate spearman’s coefficient on demos
I got it, the second, third and last terms can be written as -(a+7)(a-3) then you group the first and fourth terms by ax and you get
-(a+7)(a-3)+ax(a-3) so (a-3)(-a-7+ax)
Number 3. I really can't grasp consecutive numbers when it evolves problems like these...anyone can help or guide me to some videos or explain to me this and another related question? I really tried looking this up but other than the general method of consecutive numbers and what they are I couldn't find anything related to this. All the best, luo
Let the first number be x. Then the next number is x+1. Now the sum of their squares is x²+(x+1)²=221. This leads to the quadratic equation, 2x²+2x-220=0. Now just solve for x
omggggggggggggggg
🤦♂️
Is there an algebraic structure like Monoid, but instead of (or in addition to) a neutral element, an element e where e*x = e for all x
like 0 for number multiplication or false for boolean and
I literally dunno where to begin
If it's a hole, there can't be any dirt in it. That's probably the trick question.
Yeah I just don't know what to do with the pizza problem
combinations without repetition:
cumulate with k 0 through 10
What do those letters mean for this problem
What goes where
n being the number of toppings available, and k being the number of different toppings used for a given pizza
if you use n = 10 and k = 3 for example, you will get the different pizzas you can make when using 3 toppings, with 10 available
So can I just throw that into like mathway with 10 and 3 put in
i suppose. you have to add up the results with k 0-10 because you want all numbers of toppings.
I don't understand I'm so sorry
you put in that formula with n=10 and k=1. thats how many different pizzas with 1 topping there are. then put in n=10 and k=2, thats how many different pizzas with 2 toppings there are. add the two results. then do k=3 and add that too. and so forth until k= 10
and k=0 too
thats when you take no toppings, aka a cheese pizza.
and the exclamation mark is a factorial. i dont know how you would punch that into mathway
I can't do the math in my head or written down so I'm trying to figure out how I can do it
it's not meant to be done in your head, so no worries
Yeah I don't know how I'm supposed to do it if I don't like
Use a calculator or something
you can punch this into wolframalpha: "with k = 0 to 10, sum 10!/(k! * (10-k)!)" without the quotes
hold on a second, there is an easier way. since you have 10 toppings and for each its a binary operation whether its on the pizza or not. you can also do 2^10. should be the same result
i apologize for making it more complicated than neccessary
Wait what
That's only 1024
Hello there :) I'm not sure if this question fits the server, but it's linear alg so why not.
I'm doing 3d graphics programming and am trying to convert 3d world coordinates to screen coordinates, i.e. project the world onto the screen.
Available parameters are the camera angle in degrees, the camera position in world space, the fov, the viewport (width, height) and obviously the position of the point in worldspace I want to project onto the screen.
x and y are horizontal, z is vertical.
angle_x represents up and down movement of the camera (pitch), where moving down increases the angle -> rotation around the y axis
angle_y left/right movement (yaw), where moving left increases the angle -> rotation around the z axis
angle_z roll -> rotation around the x axis
I'm not so sure how I can express this in more mathematical terms, I guess then I would get more help as this is a pure math discord, but I hope someone still understands what I'm trying to do.
@woeful summit I thought modern game engines took care of stuff like that?
if i would use a modern game engine, yes. but where is the fun in that?
Well, I wrote code for that in 1998, which I am looking at right now.
@woeful summit do you know any linear algebra?
like matrix multiplication dot products or projection?
yeah a little i guess. this is what i tried (glm is a math / graphics library for cpp, not sure if you know how to code)
glm::vec3 world_to_screen(glm::vec3 pos,
glm::vec3 cam_pos,
glm::vec3 cam_angle) {
glm::mat4 projection = glm::perspective(
glm::radians(FOV), (float)SCREEN_W / (float)SCREEN_H, NEAR, FAR);
glm::mat4 model(1.0);
model = glm::translate(model, cam_pos);
model = glm::rotate(model, glm::radians(cam_angle.x),
glm::vec3(1.0f, 0.0f, 0.0f));
model = glm::rotate(model, glm::radians(cam_angle.y),
glm::vec3(0.0f, 1.0f, 0.0f));
model = glm::rotate(model, glm::radians(cam_angle.z),
glm::vec3(0.0f, 0.0f, 1.0f));
glm::mat4 view = glm::inverse(model);
return glm::project(pos, view, projection,
glm::vec4(0, 0, SCREEN_W, SCREEN_H));
}
idk what the project function does
it should project it correctly, modelview matrix and projection matrix.
and as model should be identity (i guess) in this case i can just pass view mat
i suspect that something with my rotation is wrong
idk computer graphics but i hope someone else can help you
Well, I seem to have neglected to comment any of my code, unfortunately.
It's an example rotating a cube.
In Java...
you could send it to me anyway (or at least the relevant part)
but i guess my problem is constructing the view matrix, not projecting as that's something glm does for me
If a direction vector is lets say t(1,2,3), then would be able to find the slope of the line?
cause if it was in 2D we could just do y/x to get the slope
Here's the Java code.
I have an older one from 1993, in C, also rotating a cube but using only integer math and precalculated trig tables.
When floating point processors were rare...
thanks a lot but honestly i don't think that helps me. it's cool to look at (i wasn't even born in 1996) but not really something i can adapt in my code
Nah, that code looks better commented though.
Anyway, the java code has a function "perspectivize" that I believe calculates a projection from an intended set of eyes onto the screen coords.
Looks like my "world" is expressed in terms of an orthonormal base, and rotation is done by rotating that base, and everything else falls into place.
||that ryme fell into place||
||
||
yeah i'm currently looking into your world renderer class so thanks already
maybe someone spots a trivial mistake in my code though. it's kinda working btw. if the camera and the object don't move, only the angle changes, it works.
What does inverse(model) do?
So, glm already has methods for translation, projection, etc?
and yes.
everything simd optimized etc. so makes really no sense to do it myself
@alpine sable Exactly how much of a circle is the part inside the lines from the center?
OK, so what's the area of the circle?
5pi cm squared
Right, so what's a quarter of that?
Divide it by 4?
Yep.
1.25
6.25
Right.
So, you have the area of the quarter circle.
Now you need to subtract the unshaded part of that. What is the unshaded part?
How do I get the shaded part?
It's the quarter circle minus the unshaded part of the quarter circle, right?
You want the shaded part of the quarter circle.
The shaded part of the quarter circle plus the unshaded part of the quarter circle is the entire quarter circle.
Right.
So, simplify.
12.5
OK, what units?
Cm
Almost.
Squared
Right.
So, what's 6.25 pi cm^2 - 12.5 cm^2?
No, be precise here.
It wasn't 6.25, it was 6.25 pi cm^2.
No, if you get a negative area, something went wrong.
What went wrong was it's not 6.25 cm^2 for the quarter circle.
Go back to what you answered for that part.
[7:14 PM] .Asante: So 25 pi squared?
[7:14 PM] Chai T. Rex: 25 pi cm^2 (units are cm^2 for area).
[7:14 PM] Chai T. Rex: Then you quarter it.
[7:15 PM] .Asante: 6.25
You answered 25 pi cm^2, then you quartered that, which is what?
6.25 pi cm ^2
Right, now subtract the answer you got for the triangle's area.
Do I solve 6.25 time pi
Yep.
Yeah, but when they ask for that, round only at the very end.
We're not quite at the end yet.
19.62
OK, what's 19.62 - 12.5?
7.12
OK, and don't forget the units.
,w 19.62 - 12.5
@alpine sable Yes, and now we're at the end, so round.
Right.
Thanks
No problem.
@alpine sable There's no rule that deals with a subtraction inside a log.
square
oh, so would it be e to the x over lnx?
wait hang on
oh, i forgot to mention, im doing diff. equations
i just tried multiplying it out to each term
but i forgot that it works diff. with logs
yea
it would be
$\sqrt{test}$
thx
Any help on this
what are you trying to solve here
x and y
oh ok sorry
Does that square thing at A mean it's a right angle?
@stray salmon can you stop pinging
i'll only give you hints but i wont give u the full answer
ok
why are you so desperate to know the answer
use y = mx + b
Use Thales
Thales' theorem, did u learn it
Any help on this
Search Thales' theorem
im pretty sure y = 0
Yea and how are supposed to find x
<@&268886789983436800> 2 ppl to 
@stray salmon stop spamming
who's the 2nd person?
yeah, they did
Cuber*
are there any other details listed in the question or is this it?
We are supposed to find the area
oh
anything else?
anything about the length AB?
Well u can find the area of the left triangle
Does the square on A mean it's a right angle?
It doesn't look like a right angle to me
most math diagrams aren't to scale
Okay lemme try
We cant solve for x right?
yeah maybe it's because you don't stop spamming and are impatient
how about you try solve the problem urself
because you keep spamming
im trying to help someone right now
with a problem
i gave you a pretty good hint actually
Please do a favor and leave this server
clever actually
B is 26.0
Dunno if angle A of the right triangle is 45
:oooo how did u do it
because 0,0 to 4,8 is 10 units
and pythagorean triple
10, 24, 26
where 10 is the shorter leg
<@&268886789983436800> pls ban cuber
lmfao
thanks again!
np
Np
how is it 10?
4^2 + 8^2
So there was an easy way to do it while we were doing a hard way lol
yeah
yh
To find the base of the right triangle we can use tan45=x/8
8*1?
U calculated?
Mh 8 then
if we rearrange x=(tan45)*8
yea
but that's assuming angle CAB is 45 tho
the question didn't state it
Now just Pythagoras or cos45=8/x
If you split a right angle in 2 angles perpendicurarly won't the 2 angles be 45
@limpid spade What is perpendicular to what?
Well we didn't need to find the hypothemuse of the right triangle
it wanted the x and y coordinates didn't it?
oh
No, only in a 45-45-90 triangle will a line perpendicular to the hypotenuse split the 90 degree angle into two equal portions, but it doesn't appear that that's been decided yet.
For example, draw a right triangle where the left leg is much, much shorter than the other. If you draw a line perpendicular to the hypotenuse up into the right angle, the left portion of the right angle will be much less than the right portion.
true
Mhhh then how is it possible to find the area
not all instances of a line bisecting a right angle will always end up with two perfect halves (i dont think that made any sense but u get the point)
we can solve the length AB in terms of x
and then find the area in terms of x
it never said we had to find the numerical value of AB
or the area for that matter
He said he needs to find the area
That would be ((4-x)8))/2
oh
can someone help me with permutation functions?
does that mean f:A>A?
actually not really 😦
i do understand how cycle permutation works but that doesn't apply to the question right?
anyone know how to prove that 3^500+5 is divisible by 14? I'm confused to how this whole mod thing works...
show that rational and use basic proof techniques for example thats its an integer and its divisible by 14 LOL
@alpine sable not like literaly lol
in proofs
hahah
i mean
@alpine sable it is divisible
isnt every number divisile by 14 then
well no
ok
????
$3^{500} + 5 = 0 (mod 14)$
i've gotten given an example to work with but its confusing me
EndTimes
what can you do with this congruence
$3^{500} + 5 = 0 (\mod 14)$
square
$3^{500} = -5 (\mod 14)$
EndTimes
$3^{500} = 9 (\mod 14)$
EndTimes
that should be very simple now
This is how to prove 5^100 − 5 is divisible by 19. I just don't lnow how to use this to prove that 3^500 + 5
*know
look at what i just did
Find the angle between the lines given by $$2x^2 + 2y^2 = 5xy.$$
abs_0
Solve for y, you should get two equations
use tangent and the slopes of the lines to find the angle
would part c be 0<x<50 or 0≤x≤50? but if its 0≤x≤50 i wouldnt have rectangle no more because there is no width..
^ping me pls
@vast lance Yes, the width would be 0 < x < 50, for exactly the reason you stated. A little more precise would be to note that if x= 50, length = 0, and A(x) = 0 and vice versa.
@solar cradle can you help me with a question
alright
@hollow flare what exactly are you studying, you can do this with a Riemann sum
perfect, that is literally the definition of Riemann sum without sigma notation lol
Just use $$\lim_{n \rightarrow \infty} f(x) \Delta x + f(x+ \Delta x) \Delta x + \cdots + f(x+ n \Delta x) \Delta x$$ where $\Delta x \rightarrow 0$.
u see i have to use definition 2
Billy Clintorus
Just define $x = 4$ and $x + n \Delta x = 7$
Billy Clintorus
yeah, its exactly the same thing
Yeah exactly!
Some early calc exercises are shallow like this, just try not to overthink it
do u know logic proofs too?
comp sci related lol not really relevant to what we talking ab but jw
I've never taken a logic course and a bit rusy on the notation so I probs can't help you on that lol
ah its fine lets try to finish this problem tho haha
@solar cradle would this be the final answer without evaluating?
yep looks good
thank you
how would i put this into an augmented matrix to solve for x, y, and z in terms if a0, a1, and a2?
wouldnt i still be able to put it into a matrix in terms of the rows equating to the t^2 coefficient, t coefficient, and constant?
example from yesterday
my professor found a way to get x and y and z in terms of a0 a1 and a2 but im so confused on how he did it
ahh wait nvm i think i got it
have u tried solving it
what did u do
oooo ummm
that's not
how u do it
have u learnt factorisation
what is this for
like what class and stuff
is this hw?
a test?
just random
?
i got the answer btw
ok
have you learnt completing the square?
for quadratic equations
what lvl of maths r u doing rn
i have no idea how to explain this
well i can't just give you the answer you won't learn
no there is definitely a solution
i already have the answer
are u australian wtf?
ohhh ok
are u like yr 10 rn?
oh
13 and you're completing the square for non monic trinomials?!
what the hell
thas weird
no just doesn't sync with the nsw syllabus
or the vic or qld one
alr fine i'll give u the solution
basically rearrange the equation so that it equals to y
how-
wdym you dont know how???
that's not the answer
but you need it in this form
then you factor the -6 out from -6x^2-12x
?????
bro are u sure youre not messing with me
well that's what i mean
when i said factor the -6 out
-6 times 2 is -12
because i factored out the -6 from the -12
so the result is 2
see how it's in brackets?
yes
oh god how am i gonna explain completing the square?
you complete the square for what's in the brackets
istg you're trolling
there's no way you could be doing this lvl of maths and not know what completing the square is or even brackets
what do you mean this year
we've only started school 2 months ago!
you-
oh
i though you lived
nvm
im dumb
anyway
fine i'll give you the solutions
hold on im writing it down
here
the solution is the bottom red box
yw
what is u
:)))

@viscid tangle this might help: https://www.youtube.com/watch?v=pwITxyUghV0
👉 Learn how to graph quadratic equations by completing the square. A quadratic equation is an equation of the form y = ax^2 + bx + c, where a, b and c are constants. The graph of a quadratic equation is in the shape of a parabola which can either face up or down (if x is squared in the equation) or face left or right (if y is squared).
To grap...
$ax^2 + bx + c = a(x+\frac{b}{2a})^2 + c - \frac{b^2}{4a}$
AMD
i'll help you out a little more
it's just a formula. plug in for a, b and c
a = -1 b = 12 c = -40
the formula will help you dw
it works
you plug numbers into the formula to get the equation
if i tell you that 2+2 = 4, then that means that any time you see a 2+2 in an equation, you can replace it with 4
now if i tell you that
$ax^2 + bx + c = a(x+\frac{b}{2a})^2 + c - \frac{b^2}{4a}$
AMD
that means any time you see "ax^2+bx+c" you can replace it with "a(x+b/2a)^2+c-b^2/4a"
because it gives you the answer
stop freaking out lol
this is a basic rule of arithmetic
called the "transitive property"
you should know what that means
if a=b, and b=c, then a=c
doesn't it?
if 2+2 = 4 and 4 = 3+1
bro
then doesn't 2+2 = 3+1 ?
both sides of the equations are just numbers
every expression is just a number
that can be evaluated for a certain value of x or whatever variable you have
what is (2+2) + 3?
hint: there's a formula for what 2+2 is
that i just gave you
right
ok
standard form of a quadratic:
y = ax^2 + bx + c
it's a polynomial of degree 2
sums of powers multiplied by coefficients
i literally gave it to you
multiple times lol
if you have an equation in standard form:
y = ax^2 + bx + c
then the vertex form of that equation is y = a(x+b/2a)^2+c-b^2/4a
so just take the a, b, and c values and evaluate
can you make this equation look like y = ax^2 + bx + c
it will
why are you so adamant on getting the answer
it's very simple if you just powered through the formula
Dragon :)
here's the answer. good luck on your test
i tried
but i guess this isn't something i can teach you
write this down line for line:
y = ax^2 + bx + c
y = a(x + b/2a)^2 + c - b^2/4a
y = -(x-6)^2 - 4
there
In a row echelon form, should the pivot point row never be swapped?
Need this to avoid my algorithim utterly evaporating the determinant
can you just use the wolfram alpha api?
i mean it requires an internet connection
but mathematica is way better at this sort of stuff
never heard of those
im using c++
and its more of a learning experience than anything
ive been stuck with this determinant thing for 2 days now
just gotta know this and im good
you've never heard of wolfram alpha
do you live under a literal rock with no internet
just don't care is all
@copper prawn you can just google that question lol
just look up a correct implementation for RREF in your choice of programming languages
or at least pseudocode and implement it into your own
but thats booooooring
if its for learning rref, really just do it by hand, if its for hard matrices use an existing implementation thats faster
its fun figuring the algorithims out yourself
oh well
best thing to do is just run the program
if i was working for a tech company
yeah
id be fired and kicked out the door by the ceo personally
but its just for fun
yea fair
hello, I was wanting to be pointed in the right direction. I have a question about statistics but I'm not exactly sure how to google it (and then watch videos to learn about it.
Pretty much pretend I'm hitting x bricks with a sledgehammer at the same force, and my hypothesis is that 10% of them will break. When can I be certain that I've broken enough bricks that my 10% claim is either correct or incorrect?
does this make sense, I can explain further if I worded it weird
ideally the number of bricks you break should be infinite
because as you break more and more bricks you get a more and more precise experimental probability
so just a reasonably large number should work
I'd want to be able to specify what p value i'd want, normally the cut off is 5% right?
yeah
Yes, I was wanting to figure out how to calculate how much that would exactly be. For instance, let's say these bricks are expensive. I'd just want to break as little as possible while still reaching the 5% threshold, or any threshold i'd set
if that makes sense
help
<@&286206848099549185> hey could anyone help me out with this?
ah this is a pretty fun problem
i may not know how to do it tho but ill give it a shot
first i think we should find the length of the arc that is over the shaded region
I don't think we need that for finding the area though
it's just the radius I'm trying to find
just multiply each coord by the dilation factor'
is the answer 416.67?
idk...?
i think thats what hes wondering buncho
whats tht?
oh for lavishes thing
I'm in grade 6 so I don't know what u mean...
well in grade 7 but failed grade 6
so back in grade 6.
o
oh, lol, well what i did was,
See the equilateral triangle? It is divided in 3 equal parts, now area of an inscribed equilateral triangle is (3*sqrt3)/4 *r^2, so i calculated that, and then, calculated the area of the segment and then added them both
..........
whats a sqrt?
square root
sqrt=square root
how do u just know the area of an inscribed equilateral triangle
i studied it for olympiads
idk of any way simpler than this
oh
like anything else would be more complex, with trignometry, or some wacky geometry properties
ig
lmao
oh @upper ember is there a way to find the area of a triangle without the base?
well, there can be
like there is a formula, area of triangle=1/2 ab(sIn(C))
but u will need to know one of the lengths
then u can use some neat tricks to find the area
this formula uses trigonometry, btw so dont be confused if u dont get it
Not sure if this is correct but I feel like you can prolly just find the area of the circle and then divide by 3
Because if you look at the image the unshaded area is actually just the same as two of the shaded area
tht wouldn't work i think
why not?
cause it'd be like 3 pieces of a pie then
I could find the area of the circle then triangle then subtract them and divide the answer by 3 tho
But isn't a part of the triangle also shaded in?
i can find that after dividing the triangles area by 3
ok
Technically speaking couldn't the situation be like this?
https://share.sketchpad.app/21/20c-5280-1b50bf.png
The question doesn't actually say anything about symmetry
I think that it's pretty safe to assume that the diagram provided is at least accurate if not to scale
do i set the determinant to 0 for this?
That would make one eigenvalue zero
For repeated eigenvalues you'd probably set the discriminant of the caharcetrsistic equation to 0
i mean discriminant not determinant sorry
k well that answer is wrong
One possibility is how you're entering the answer.. These autograders can be really eccentric
nah it entered correctly
Well, that was my last idea.. Sorry
I have a question
what
d/dx lnax is just 1/x right
yes
So it doesn't matter what the coefficient is
no it does
it would be a/x
d/dx ln(ax) = 1/ax * a right?
Wait hold on yea by chain rule
Because after all, ln(ax) =ln(a) +ln(x)
oh your right
And ln(a) disappears
fuck
Lmao
dln(ax)/d(ax) × d(ax)/dx
Base times height
well if u=2x+y, du/dx=2+dy/dx, so dy/dx=du/dx-2. then, du/dx-2=u after subbing everything in. The resulting diffeq in u is seperable
Ohh got it! Thanks a lot!
Can I get some help with question 12
Since I have the symmetric equation of the line it's parallel to, I know what the direction vector is
But not sure how I would find x_0, y_0, z_0
hey, could somone help me out with these equation ? Whats the reason or definition of multiplying the transpose x with x and the inverse of it ?
i also would appreciate if you suggest somethin that i can study that on
that's the solution to a least squares problem @serene jacinth , you can find it from $\min_{\theta}\Vert X \theta - y \Vert_2^2$ by taking the gradient and setting it equal to 0
Edd
you can look at multivariable calculus, linear algebra, optimization, signal processing, and/or machine learning to read about it
the "reason", from the linalg perspective, is to project the vector y onto the row space of the matrix X, since that bunch of matrix operations yields an orthogonal projection matrix
Do you know how the derivative is defined
i dont understand what youre asking
ik how to find the derivative of like
2x^2 or something like that
but not when its like 1+ 2x^2
but do you know what the derivative means
yes
the derivative of a number is just 0
then what's the problem
idk how to do the problem


