#math-help
1 messages · Page 8 of 1
PLS explain this to me
This is a really fun one actually
Let me show you
Have seen hyperbolic functions
You could graph it and use hyperbolic functions
X-axis should be -2.5 and 2.5 my bad
Hope this gets you on the right path, good luck
i dont know how to continue. should find the minimum of the function by derivating it? whats the function? or should i go by a triangle and find the angles/sides?
As i said, hyperbolic functions
If you the function you derive it to find a min or max
<@&942391219206647828>
ah i get it now. I didn't learn those functions yet i look it up. Thanks g
Oh you havent seen those functions yet?
ye, that problem i saw on the internet somewhere and i tought it was simple but i couln't get it right, so I asked you
Oooo
Yeah then its to do with hyperbolic functions
Idk if you have the solution? You can check if you want
@trim saddle is the answer is 0.88 or 1 ?
i dont know ┐(´・c_・` ;)┌
thats sad it took a while for me though
Soo, when will you get the key? @trim saddle
im sure there are different ways on how to approach the problem
i just thought hyperbolic functions were the best approach (imo) but sure you can solve differently
maybe even trig functions
trig aint useful here
how come
chatgpt solved with a simple Pitágoras theorem, but i think its wrong
curves and all
you could rescale everything so they are part of the domain
but yeah gpt said close to .88 too
transformations

damn
I did use hyperbolic functions though
😉
we got it so thats the most important part!
YEah!!
dunno man :(
i dont know if you are seeing derivatives etc but i can give you a tip: if you are asked to find a min or max of like a volume or surface,...
you can (always) like most of the time, solve those kind of problems with graphing it with x and y coordinates
yeah i use that
Well one of this type was asked during the interviews conducted by amazon
o for real?
for what role?
thats sick yo
cs stuff?
yeah cs stuff
it wasnt this hard, but a logical question which can be answered in seconds if you really use your brain
and dont overthink the question xp
ye they do that
cuz stress can do mad stuff
@trim saddle ayo le me know if you get the real answer(key)
i cant get it. that problem was an image from 4years ago. idk the user
damn, you do have good memory though
man i did memorized it. i was searching and found it. sorry i dont have the answer
Well I was appreciating your memory power nvm
i shared with you bc i didnt have the answer too ehehe
Hi guys
How would you have solved this system with four unknowns and what parameters would you have chosen to change the variables?
thanks for the help
This is how I would have done it, which is very similar to your solution.
Thank u so much
Hi how would you do b)?
I dont think my answer is correct, as for fg(x) i got (x+3)^2+2
Does the range belongs to (2,infinity)?
yea it does
can anyone please solve this? ig i am doing calculation mistake
option C ?
<@&942391219206647828>
Hi, does anyone know what formula to use to solve the cross product of two vectors that both have two points in a 3d space? All I can find is how to calculate for vectors which have one point. Or do I somehow choose which one of those points to input in the formula?
okay thats what I got, thanks alot
two points?
cross products are normally just done with the vector components
well i'm asking because i'm doing a thing for programming, and the task we're given has you create a vector "with two points" so each vector has such coordinates stored in an array - x1, y1, z1, x2, y2 and z2. One of the functions i need to implement is a crossproduct of two vectors. I think I understand how to do it normally, but this "two points" part is messing with my understanding
Anyway, I think I'm on the right path, i think the description our prof gave us "vector with 2 points" is instead meant to be a line segment. And then I would need to get the vector from that, and then calculate the cross product. Does that make sense or am I still doing something wrong? If it does, then I've solved the mystery, otherwise someone tell me I'm tripping
hey guys, can't figure out how to form the equations for this problem, i get decimals with mine 😭
boys = 11
girls = 16
i didn't get how to make the equations though
and the answers say 11 and 27 ┐(´ー`)┌
yep
tysm!
OH MB, didn't pay attention
can someone help with this co-ord geometry question pls🙏
Why we’re taking [1/2;inf) as an answer?
@weak lotus sorry for disturbing you, but maybe you can explain?
2 says x has to be larger then 0,5
or equal to 0,5
everything larger then and equal to 0,5 = 0,51,0,52,...n
with n = infinity
@maiden epoch
but we also have 0>-1 in 3
so why we wont include -1?
because zero is always larger then -1
and
you need all solutions
i think you can have nr 4 to
-x >= x +1
3 numbers giving the answer tho
number 1 is false as you did above
number 2 is x being larger and equal to 1/2 so till positive infinity
BUT
0 is always bigger then -1 and 0 isnt a variable its a constant
you need to know the values of x which is a variable and thats for (1/2; + infinity(
got it now, but got confused here again
interval ends on -5/6 because it must be bigger then x? or?
do not include -5/6
well this can be simply solved by symmetry and all
Well its the real method, If you want it
I don't understand this formula:< can someone help me with it
hii, can someone explain this to me? im watching a class video on how to solve it but i just don't get it
A)
wait,,, can we write x+1 like that??
Can someone help me! My teacher teach me Dijkstra's algorithm, and this is a example about it. I just don't know how my teacher write this table and how it work?
Use pemdas
Hello can someone help me in the last equation why the right hand side is one?
book= fundamentals of wave phenomena, akira hiroshi page 149
tysm !!!🙏
I don't see any zeros here
tyy
sorry i meant 1
but i already figured it out tho
Anybody studies math in french?
I do
Anyone can solve this question?
pi/2?
can someone help w this differentiation and integration q pls 😭
both if u could 🙏
4 and 5?
THANK YOU SO MUCHH !!🙏
does the 3rd term really has power 3? or it is a printing mistake?
if it is a square then the answer would be around 44.5
use Cos(90-theta) = Sin(theta), you will get 44 pairs of(sin^2(theta)+cos^2(theta)) and a lone term sin^2(45)
can you please explain the working?
Well do you know the formula for Sin^-1 (X) + sin^-1y ?
Tbh, you can take any point on the circle in the given equation and substitute in arc sinx and siny
pick (1,0) xD
Probability calculations:
P(B|¬A) = 1 - P(¬B|¬A)
Is this correct?
Thank you so much!
think about the maximum and min values of arcsin(4x-1)
the max value of arcsin corresponds to max value of y and min to min value of y then u have the range
damn , nice way to help, rather than giving answer, u are making him think. I like that
we all should do it that way only
I have seen many people asking for fully exam like written answers
even though I have sent them the explaination
yeah i mean straight up answers dont help much methods do :>
as they say.Give a man a fish, and you feed him for a day. Teach a man to fish, and you feed him for a lifetime
Hi can someone help with me part a)?
I use u = 3+2x
but the worked solution gives me this as the method on how to complete
I understand the concept of where the u-3 and the 2dx being replaced by du
but I dont understand why it becomes over 4
any help would be appreciated 🙂
x=u-3/2 and dx=du/2
the 2s get multiplied
im so stupid thank you so much
I got so confused by the mark scheme saying 2dx = du
thank you so much
nahh it happens to everyone
put x=sinu then dx=cosudu then it will be sin^2u * cos^2u du = (sin2u)^2 du then you can just turn it into cos4u
Hey everyone hope you're doing good. I'm studying Statistics and Probability in Maths if someone can help me with resumes or courses about Probabilty. Thanks 😁
Whach u need ma man
The basics how to calculate a probability and random probability
Let me share you a link because my native language is dutch
In this video I will show you a great book on probability and statistics. This book can be used by beginners but it is not the easiest book, and also certain examples do use calculus. This book is usually used in courses targeted towards engineers with names such as "Statistics for Engineers". If you want to learn statistics or probability and w...
Khanacademy is really good to
Please help
Language?
It takes time+ do more problems
Practice makes perfect. Start from the bottom. Make sure your fundamentals are ON POINT. make A LOT of practice problems. The more you do, the more you learn, the goal here is to connect neurons and the more neurons arz connected, the faster you think!
all the points that can be represented on a graph denote a real number, right?
well there is a plane called argand plane, where imaginary numbers are plotted
Do you graph functions on the argand plane? 💀
well, if its complex numbers then yes
Hi, I'd like help with a very simple problem...
A DVD production cost is 25 euros. When the factory sells one unit to a store, it makes a profit of 40%. What must be the selling price of the DVD so that the store makes a profit of 30% ?
i completely forgot how to do something like this 
Thank you!
yre welcome
can anyone help me with this differential equation
I am a three-digit number,
The sum of my digits is 7.
Multiply me by 5,
And you'll reach a number that's alive.
Add 200 to that number,
And the result you shall uncover.
The number you get after solving this puzzle is smaller than the main number (Guess the number)
Riddle number < The correct number*
2nd Hint for stage 1(Gues the number) :-
(500 + 200) - (400 / 2) + (150 * 2)
The number you get after solving this puzzle is Greater than the main number (Guess the number)*
Therefore if you get the solution to 1st and 2nd riddle
1st Riddle number < The correct number < 2nd Riddle number

Is this all of it?
I get two answers
It's worded so oddly but I'm assuming that
1st Riddle number = 'x' (sum of digits = 7)
Correct number = 5x + 200
2nd riddle number = (500+200) -(400/2) + (150*2) = 800
That gives x<120, which gives x=106 or x=115
And then the correct number would be 730 or 775
use substitution method
x^2 = t
Thanks mate.. i also got the same ans
yeah we can do in that way too
f is injective
is equivalent to
there don't exist pair of different values x,y such that
f(x)=f(y)
f(x)=f(y) is equivalent to
(x-y)(x²+xy+y²-1)=0
so
there don't exist pair of different values x,y such that
(x-y)(x²+xy+y²-1)=0
which is equivalent to
there don't exist pair of different values x,y such that
(x-y) = 0 or
(x²+xy+y²-1)=0
which is false
because x²+xy+y²-1 can be 0 when x≠y
Hello can someone help me with math problems?
Post it here@left knoll
Find the temperature distribution in a semi-infinite plane with a width of 20 cm if the temperature at the bottom is 𝑇 = 𝑓(𝑥) = 𝑥, and the temperature at the other edges is maintained at 0 degrees.
can someone help me with this problem? thanks
as far as i know there's some psychology scientists invitend laws like that
there's :the subjective sensation is proportional to the logarithm of the stimulus intensity.
i don't know about this one tho lol
Since ABC is a triangle [AB] is a bisector of this triangle, and DEFK is a square, find the angle measure DCL
can you draw it again?
i cant really see the lines
X?
and shoudnt it be (ad) as a bisector
isntead of ab
thank you very much!
i see what you need to do
ill give you a tip wait
You can use this
@weak lotus Thanks for everything I found the solution to the question from another friend of mine
It was difficult to understand what they were saying because my English is not perfect
oooo
all good man!
geometry is pretty versetile, a lot of ways to get to the answer
good luck
kinda stuck at this question, can someone help?
simplify: lim (x->0) 4*arctan((x+1)/(2x+1))-pi/4x
Then we use L'hopital: lim (x->0) (-4/(5x^2+6x+2))/4
Plug in 0 for x: (-4/2)/4 = -2/4 = -1/2
for osme reason when i put "Factor 3x^2 + 4xy + y^2" into my CAS it just comes up with the equation as the answer
anyone know how to fix?
the answer ik is (3x+y)(x+y) but it dont show on the cas
prove that x^4+4 is prime only for one value of x belongs to natural number
İ find it by trying , can u post the solution
r u sure 💀?
ya
X^4 + 4 = 0 ?
no let me write the entire stuff
x^4+4=x^4+4x^2+4-4x^2
(x^2-2x+2)(x^2+2x+2)
what to do next
Ths 0 = 0
BRO
FRЕЕ GIFТ DISСОRD NIТRO - https://cutt.us/takefullnitro
omg BRO 😘
guys
in the vertex form formula: y=a(x-b)^2+k
what does k equal to? in quadratic
Çok tesekkurler
rica ederim 🫶🏻
equals to vertex
you mean the y value of vertex?
yep
b is equal to half the sum of the roots sooo coordinate (b,k) is the vertex , ı hope ı cn expln
and we also can say axis of symmetry to b
🫀
is there any way or any math symbol that can denote modified factorial operation,for example 6!=6x5x4x3x2x1x0 but i want this way (6x5+1)(4x3+1)(2x1+1)?
or can i use substitution for example k! where k is k(x)
Why not just write Prod_{k=0}^{5} [(k+1)k +1] with Pi symbol for product
yeah i never know the name of capital pi before, or any ideas what is that symbol, thanks
Can I theoretically reduce any improper integral of the second kind to an integral of the first kind (to generalize the convergence criteria) using substitution and integration by parts?
Can someone dm me asap if they are able to help me with quadratic functions and equations, trig, rational and reciprocal functions, systems of equations and inequalities, and substitution and elimination (if you can help me with one of them please dm)
True?
well you can take 1+x^2 = t
Still you will get the same answer mentioned above
Which kind of help do you want in them?
Hii im studying physics and i was doing really well until this
translation: "calculates the force (module, direction and sense) that will act on the conductor" The thing is, i dont understand why the sen is 90° and why the result is written like that?
other than that i understand it, but the guy in the video doesn't explains the questions i made 

@left knoll THe length vector is along x axis
and magnetic field is along z axis
so alpha = 90
As dream suggested you take u as 1 + x^2. You have to make it yourself as easy as possible. Good solving but time is key 😁
Use the hand rule!
Aigt
for b) (i) you use the answers you get for a) which are (0,3) and (3/2, 0) to find the values for a
to get the first value of a you set y=ax+2 to 0=3/2a+2 which you end up getting a =-4/3
but for the other value of a you need to do (y2-y1)/(x2-x1) = a to find the other value for a
but how do you know wether is (y2-y1)/(x2-x1)<a or (y2-y1)/(x2-x1)>a ?
you cant directly keep the value in it
since we dunno whether it intersects at the same point
yea so its gonna be a< -4/3 or a > -4/3
yeah
but i dont know which one its gonna be
take union
well i do because ive seen the mark scheme
both can be done
what union?
the way I think of it is for when y=-2x+3, a > -4/3
and then a < 2 for when its y=2x-3
yea
shouldnt it be x = 1/(2 + a)
really?
cause when 3-2x=ax+2
oh yea my bad i was thinking of the next step
ohh
well if -2/a lies in the negative side then
-2/a < 3/2
so a>0
typo error mb
but wont a = 2
because to work out the two values of a
firstly you do (y2-y1)/(x2-x1) = a
slope isnt it?
which you end up getting -2 = a
yea for when y=2x-3
can you send your rough work?
yea sure give me a sec
a = -4/3 for the left side *
I think the set of values for a is
-4/3 < a < 2
Because rise/over run has to be less than a
As then a will become a < 2 instead of a > 2 because then we get no upper value as we -4/3 has to be the lower value
If that makes sense
can I ask you why did u take y=0 and x= 3/2
well y=0 and x=3/2 is the poi of the one of the equation
yea its where x intersects the y axis in y=-2x+3
and i used it cause then you would have 3/2=0*a+2
and then you cant find out what a is
nahh man it aint the poi of the unknown equation
it doesnt even pass through it
idk, you cant use it like that
oh bruh so i used illegal maths
yeah fr xD
@fiery widget you can use this for getting the range part though
the question asks for domain, would I still be able to use it
wouldnt I just do
2x-3=ax+2 and 3-2x=ax+2
and then work out the individual x-coordinates of in terms of a
yeah
you can do that way
okay cool
thanks alot, even thought I ended getting arrested by the maths federales
appreciate it
yeah u can
it will something like a belongs to (-infinity,-4/3) U (0 to infinity)
you're studying for neet right, why did they gave you maths hw? (if u dont mind)
well take cases for each quadrant to find out the answer
Hint:- check in 4th quadrant
Use Euler formulas
Appreciate it
How do I now if the given vector set is spanning or not if the set is not an square matrix. For example a R^2 but with 3 vectors?
v₁ = [1, 2]
v₂ = [3, 4]
v₃ = [-1, 0]
what is the definition of a spanning set of vectors?
is it these theorems
do i need to turn it into a system of linear equations and solve for x, y, and z?
according to the definition, number of vectors doesn't matter
yes
there will be infinite number of solutions
question if I were to turn the vectors in a matrix
1 1 -1
2 3 0
and using by gaussian elimination, the answers are
x1 = -3
x2= 2
does this mean it is spanning?
you need to solve system of linear equations
ii don't know how you can apply gaussina elimination here
you have system
x = a + 3b - c
y = 2a + 4b
solve it however you want
including gaussina elimination
but it is simpler to solve it as usual
with substitutoin
Could someone help me out with 1(c)?
Look at moment generating functions for normal distributions and then connect them with the normal CDF
can someone tell me why this is not a function?
is it because y is ^2?
The equation (x^2 + y^2 = 1) represents a circle, an equation for a circle can’t be a function. In order for an equation to represent a function, each input value (x) must correspond to an unique output value (y).
If you solve the equation for y, y = +- sqrt(1-x) there are two possible values of y for a given x. So yes it’s because of y^2
how do you know if it represents a circle without looking at it on a graph?
sorry I don't understand this
I'm very bad at math
But i managed to understand how Function represented as ordered pairs work. same with Mapping Diagram
Now im trying to understand function represented as "Equation"
but the video tutorial that I am following on YouTube failed to explain it to me
I only know that if the vertical line intersects more than one in a graph, it is not considered as a function. btw this math topic is called Functions As Models
what do you not understand
have you seen implicite and explicite functions?
that explains when a function is a function or not
if we can write a function in only one way like y= its mostly a function
but if its y^2 we will have more outputs then we are allowed to generate
a circle is not a function because if you draw a line perp to the y-axis is crosses the "function" twice
its a graph, not a function
I haven't
Can you recommend a YT video abt it that will help contribute on my understanding abt functions?
ill search one wait a sec
Difference between explicit and Implicit functions, Dependent Variable, Independent variable, Changing an implicit function to explicit.
Send the Sol if you do...if you wish
that is
what is written says Is because we dont know the sign of the term (x+4) we cant take the solution -5, i wanted to know how one can know which solution goes (in this case is -1), because the two of them are negative, the problem would be that we dont know with certainty the sign of the x right ?
@versed gyro They tell you in (a) that your house is TWICE as old as your neighbors house
… that’s all the info you need really
you substitute them in the original equation
check
√((2•(-5)+11) +5-4=0
if true then -5 is the solution
Hey guys, a quick question about determinants and eigen values, if I have the characteristics equation Det(A-Iλ)=0 and I preform rowoperations on matrix A, how do I keep check of the determinant? am I even allowed to do row operations on matrix A?
becuase the determinant is not closed under addition
Alright, already figuerd it out!
Hey pal, can anyone here recommend me a crash course in microeconomics? I really want to prepare for next semester, but I don't have materials and have no idea where I can find good ones.
Hiyaaa if you tip in yt : AP microeconomics full course you get a handfull of good linkd
BRO
FRЕЕ GIFТ DISСОRD NIТRO - https://u.to/0E67Hw
you mean monotonic?
nope basically
leading coefficient will be 1
did you tried by substituting the given values?
well try writing it as f(x) = g(x) - x
damn it would be easier if they have given the value of f(6)
its 3am here, I will try this question in the morning see ya
Did u get this?
f(x) =x⁶-15x⁵+85x⁴-225x³+274x²-121x
here's the funtion
by the definition of a monic polynomial, a₆ = 1
so your polynomial has form
f(x) = x⁶ + a₅x⁵ + a₄x⁴ + a₃x³ + a₂x² + a₁x + a₀
@torn trellis
ohhhhhhhhh thank you so much @surreal cypress
sure
anyone good with calculation of physical chemistry
Anyone know the simplest way to simpify this without the use of a calc?
Looking how I can make this into sq(3/2)
Thanks, I feel quite dumb now that I see it
Appreciate it!
anyone know how to split into those two brackets?
Can someone help me? I make the substitution but I think I make it wrong
x= 16tan^2z
ig that will solve it
you need to take the determinant of the matrix
do you know how to take the determinant of a matrix?
yep solved!
You also say that the whole square root is equal to u and do the whole substitution
Solve for x and fill in
Simple as that
yo thank u very much!! it took me a while to understand it but I did
got you, best of luck
Hey can someone help me out with question 2?
I got 2a+h^2 +2a
But it’s not on the choices 😭
I feel like I did something wrong
But idk ahh
How?
OH
I’ll try again 👍🏽 thank you @surreal cypress
not sure if you still need it but here’s how i did it and got the answer
Thank you 🙏🏽
no problem :)
sem problemas
can someone tell me how the mandelbrot set works
can any one explain the marked step
Is any one a med student here
@onyx yoke check the medic-help channel
Thank you!!
Its already explained
S = 1/(1+x) + 2/(x²+1) + 4/(x⁴+1) + ... +
S + 1/(1-x) = 1/(1-x) + 1/(1+x) + 2/(x²+1) + 4/(x⁴+1) + ... +
S + 1/(1-x) = 2/(1-x²) + 2/(x²+1) + 4/(x⁴+1) + ... +
S + 1/(1-x) = 4/(1-x⁴) + 4/(x⁴+1) + ... +
S + 1/(1-x) = 8/(1-x⁸) + .... + ...
U can add anythjng to both sides of any equation
for example x + 2 = 3
i randomly decided to add x to both sides of the equation
the equation remains equivalent
can add 1/(1+x) to both sides because I want so
x + 2 + 1/(1+x) = 3 + 1/(1+x)
in this case theres the equation
S = 1/(1+x) + 2/(x²+1) + 4/(x⁴+1) + ... +
you decided to add 1/(1-x) to both sides of the equation
Need any help...maths genius is here
youv solved a millenium problem?
not yet but tryingg....
you know you need a whole squad for that right?
what problem you trying?
Are there some experts at modular arithmetic here?
The next term in sequence 1,3,6,11,20,37,?
options are
(1) 65 , (2) 67 , (3) 70 , (4) 60
with explanation please
Hope this helps
3rd line is x2 so after 8 we have 16
16 + 17 = 37
And thats correct
So 16 × 2 = 32
2nd line is plus 1, 2, 4, 8
So that gives us 16
Plus 17 = 33
33 + 37 = 70
Answer 3
how many hours should i aim for to learn all of precal
it depends very much on your current knowledge in functions and analysis
are you still in high school? if so that might take couple of weeks with constant studying
but if you've already graduated is more simple
Going into 11th grade and have knowledge in Algebra 1 & 2 and geometry
Everyone be advised please try to ignore this it is a scam as you will click it it will take on your person information be aware of your surroundings please confirm before clicking on the link. I'm just a random who came by to know that this is a scam, just spreading the word around.
Could someone help me please, thanks 👍
Everyone be advised please try to ignore this it is a scam as you will click it it will take on your person information be aware of your surroundings please confirm before clicking on the link. I'm just a random who came by to know that this is a scam, just spreading the word around. As i have said before about some other spam with same info too.
Hmmm looks like math to me
Hello can someone please help me in any of them
this one is the hardest of them, just follow the same idea and the rest shall be easy
Hi, i am a beginner at math, can someone help me?
One question, If between the parts of the equation there were * (also if it would be a multiplication) than you proceed as usual (multiplicate the normal part and add the exponents)?
What you need
a shape made of 12 cubes
how many different ways to go from point K to point L using the shortest path?
is it 210?
my solution;
7!/2!x3!x2! = 210
@calm galleon
LOL my guy just <@&1050536614306267217>ted the man himself looooooooool @left knoll
solve the question
is it 210
Yes, always try to find the simplest expression before you actually do the derivative, it helps a lot
Guys I need help
For what value of the variable will The value of 3 - 5c be 1 less than the value of 1 - c
3/4 ?
is the question that simple or c is some higher like academic term stuffs that i have no idea about lol
I think it's just 3/4 yeah
3-5c + 1 = 1 - c
-5c + 4 = 1-c
-5c + c = 1 - 4
-4c = -3
c = (-3)/(-4)
c = 3/4
Use derivation and ricos
Slope my bad
Thought the dutch word was the same as the english one
Ohh 😂
You use derivatives to find minima and maxima
Ohhhhh
Oh yeah if you find minima that’s how you get question b
The SAME is also a hint
😂😂😂
That means they are EQUAL to eachother
C and d is just knowing what they ask and what your function tells you
So I equal them together and get the x?
Jup
Im not gonna give the answers because thats not how you learn, so try it yourself! Im sure youll get there 😁
Ohh I substitute for that
Nono thank you sm! I prefer that way too :)))
Thanks you helped me a lot I’ll go attempt the question again!!
Got you! Best of luck
hello, does anyone know how to count area in between curves using integrals? :((
like acreage ?
just let two y equal, you will have x^2-9=3x-x^2
solve the equation
then integral the absolute value of 3x-x^2-x^2+9 with thoes two x you just got
use your calculator tho
u can also use the geogebra method to check results!
also thank you very much 
okay everything here is fine and i understand the process but 1 more question why i subtract x^2 - 9 from 3x - x^2 and not other way around?
to be fair subtract the other way around will give you the same anwser since it in absolute valute, however you would like your mindset to let the above one subtract the under one
like in some implicit function problems you should always subtract the above one to the lower one cause some question wont trick you but some will do so even if it gives the same result just subtract the above one for the lower one, just to be safe lol
somebody studying linear programming?
the solution to this question is to solve for x in terms of y using the quadratic formula. But what would happen if you solved for y in terms of x using the quad formula? I tried this but I ran into some problems which to me doesn't make much sense cuz it's the same idea. Can anyone explain or help me with this?
You can change the order of the incognits how you want to as long as you respect the value of each one of them. It would be the same as pretending x is a and y is b or vice versa
In short, the difference is that when clearing a variable, you are saying that this variable is the dependent one. That is why the values would not be the same if you do not respect their meaning
Also the quadratic formula is to find the roots once you have already simplified it all. If you pretend they're y you're basically searching a 2 tigers in the ocean lol
Hope that helps
what's the answer
(x,y) = (1/3,2/3) is the only solution
So basically since y is an independent variable and there can be multiple of the same y values within the function, therefore solving for y in terms of x doesn't work?
oh im getting none
the solution is pretty weird
oh makes sense
If you make Y an independent variable, means your looking for it's roots so it would be valid solve it in terms of x. But you would have to change all the values and it would only take you more time
In this case you would have to make 5 a 2 and 2 a 5 for X^2 and Y^2
Basically something like his and then you solve?
Cuz that's what I had in the beggining
But when I tried to do quad formula on it the discriminant had an unfactorable equation
f off
hello
Thank you I understand it a lot better now 😅😅
Anyone know how to find x?
sorry for the bad picture quality
hope it explains 🙂
Help please I need to answer question 4 in 30 minutes can you help me?
Hi, is there someone that could help me to finish a three phase exercise (electrical engineering stuff)?
I'm stuck and don't know how to continue it
?
this cost matrix assignment problem i need optimum cost and right circle
use translaate
I dnt speak turkish
its not about translate I gave enough information for someone who might know how to solve
https://www.youtube.com/watch?v=y9r_LuZy_zI another example
Method to solve Problem (Hungarian Technique):
Consider the objective function of minimization type. Following steps are involved in solving this Assignment problem,
- Locate the smallest cost element in each row of the given cost table starting with the first row. Now, this smallest element is subtracted form each element of that row. So, we...
Probably just write the absolute function as a normal function and then calculate them
I think
case 1: 3-x ≥0
y= 3-x
x = 3-y
inverse function f-1(x)=3-x
case 2: 3-x<0
y=-3+x
x = y+3
f-1(x) = x+3
inverse function f-1
f-1(x) =
3-x if x≤3
3+x if x>3
thank you @lime yarrow
it's one function and it's called piecewise function
np
F-1(x) is swapping x with y and y with x. Solve for y and determain for what x values the function exists
So you get an rational function
domain of f-1(x) is range of f(x)
I've been stuck on this physics problem for hours now so if anyone could explain how to calculate this it would be of much help
I think the first one should be I = m1 * x1² + m2 * (x1 + x2)².
And for the second one you need the "Satz von Steiner" (I don't know the english translation and I can't google search because my Internet Provider is Brokey Mokey). Basically, you take the moment of inertia for a rod when the rotation axis would in the middle (search for the formula, should be I = 1/12m * length_rod²) and just add the additional Inertia I = m_rod * d_Offset², where m_rod is the mass of the whole rod and d_offset is the distance from the middle of the rod to the axis. Not 100% sure as I had to do this like a year ago when I still studied mechanical engineering. But this should be right
I agree this sounds right
But I tried the exact same equation for the first one and the result is super duper small and says incorrect
yea i get 6.1394*10^-5
for the first one
Welp, imma try it myself gimme a few minute
thank you sm 🙏🏻
inb4 its wrong because your prof does some weird rounding shenanigans 💀
omfg that COULD be it
happened in the past
fucking professors
that was it
rounding
im gonna kms
welp
no problem lmao
yes yes
I do understand ax^2 + bx + c > 0 graph will have it's parabolla in such a way that it won't cut the x axis for the eqn to be > 0.
There the discriminant, D<0
But the thing is if D<0 then the question says that the roots are real but if D<0 then it's roots will be imaginary and imaginary are not real
where does the question say the roots are real?
Discriminant Nature of roots
D = 0 Real and equal roots.
D > 0 Real and unequal roots.
D < 0 Unequal and imaginary
For the equation ax^2 + bx + c = 0, the discriminant is given by D = b^2 – 4ac.
First understand this and then memorize it. Use flash cards or cover parts of it with hand or page to help you memorize.
can anyone help with Vu and Vi? how is it calculated... B=2pi and T=-1/3, and im not sure what of the value of y from the question.
hoiw do you know that member a is going clockwise
cbse?
hii, can someone please help me with the concept of percentage and money related stuffs? im stuck on this question : Price of a car is reduced by 20%. Sale is increased by x% and output is increased by 25%. Find the value of x.
hmm im gonna try breaking down the problem step by step
first, the price of a car is reduced by 20%.This means that the price is now 80% (100% - 20%) of its original value.
then, the sale is increased by x%. Let's denote the increased sale as S. The new sale will be the original sale plus the increase, so it will be S + (x/100)S.
The output is increased by 25%. Let's denote the increased output as O. The new output will be the original output plus the increase, so it will be O + (25/100)O.
Now, we need to find the value of x, which represents the percentage increase in sales.
According to the problem, the price reduction leads to an increase in sales and output. Therefore, we can set up the following equation:
(Price of car after reduction) × (New sale) × (New output) = (Original price) × (Original sale) × (Original output)
Using the information we have, we can substitute the values:
(0.8) × (S + (x/100)S) × (O + (25/100)O) = (1) × (S) × (O)
Simplifying the equation:
0.8(S + (x/100)S)(O + (25/100)O) = S × O
Expanding the equation:
0.8(SO + (x/100)SO + (25/100)SO + (x/100)(25/100)SO) = SO
Cancelling out the common factors and simplifying:
0.8 + 0.2x/100 + 0.25 + 0.2x/400 = 1
Combining like terms:
0.8 + 0.002x + 0.25 + 0.0005x = 1
Combining the numerical values:
1.05 + 0.0025x = 1
Now, we can solve for x:
0.0025x = 1 - 1.05
0.0025x = -0.05
x = (-0.05) / 0.0025
x = -20
Therefore, the value of x is -20.
oh this makes much more sense woah thank you for the effort
but the value of x given in answer key is 56.25 % :(
either im not able to interpret the question or doin sum wrong
Ya
OK EZ u just needa be disciplined in doing math, do ncert 3 times (once in school, once as school homework and one as practice) giving special emphasis on proof questions + examples in ncert. after each chapter do rd (not everything but cover ALL different patterns of questions) and get ur doubts clear then and there DO NOT hesitate. that's all u needa do also better focus in class
oh:(.
use the pigeonhole method/principle
Yes as he said do ncert multiple times
I scored full in 10th
Not exactly full
Should'nnt P(7) be 6/36 and P(11) = 2/36? Ik the answer is correct but ii don't understand how P7 and P11 have equal favorable cases as shown below
yes
<@&942391219206647828>
the above links are in every channel
fake youtube links i think
got it
Hello I am looking for a math online course can someone recommend any?
Omg right.. thank you so much
need help from someone to explain me why does it turn into this
@ me if there’s a part you don’t understand
atleast they took the effort to type it in gpt 💀💀
Yep
it's like they never knew about it
right
OH OMG thank youuuuuu
Hello
¿Someone here have a proof of why cos(2x) = 2cos(x)^2 - 1?
can someone help me get why x >-1 matters
so that the number under the root is not negative
Why the limit of (1+1/n)^n as n approaches infinity is e?
Why the limit of (1-1/n)^n as n approaches infinity is 1/e 👉 https://youtu.be/C16mHM3b8Tk
Mathematics discussion public group 👉 https://www.facebook.com/groups/292419116266033
open for questions asking 🤗
To suggest/request a topic, kindly click and visit https://learnprecalculusonline.b...
The goat
hey - i know how integration by parts for indefinite integrals work and i also know what definite integrals are, yet i don't understand the following:
why are we allowed to just adjust the integration by parts formula so that it looks like in the picture?
Im not entirely sure I understand what you are asking
Are you asking why the bounds appear where you have highlighted?
If so, you might want to refer to a derivation of the method and/or a proof of why it works, if you want to understand it in depth
Or are you asking why L is used?
someone help me
how do you find the square root of 573800 ?
calculator
yes
yes well i have never (before solving a certain exercise which requires it) seen the rule before - does it have a name? or how can you derive that rule?
if you are required to solve it without a calculator, then you can find the prime factorization (it may just take some time to calculate some of the stuff by hand)
you can find the derivation for IBP readily online. then, take their derivation and apply bounds to it
My point is I don't know how to "apply bounds" to it
I have doubt can I hear music while solve math problem
yess, it was an exam
university entrance
the problem was like this: basically, we got the surface area for the pyramid and we need to find the side lenght
I don't know the exact problem but sometimes you can avoid having to work with roots, e.g. instead of Pythagorean theorem you could use intercept theorem
ty!
ez learn long division best method
well, when doing the derivation of integration by parts, when you’re doing something like taking a derivative, evaluate the derivative at the bounds
or when taking an integral during the derivation, do the same thing
the derivation will be the same
this
limx->3 = -3+2 = -1
this one is cancelled out
limx->2 = 2
-1 + 2 = 1
Then the answer is 1
p
i was able to derive it, thanks
Abhi_Codz: Status
**afk: **
Tomorrow's my math exam lol
Wish me luck for preparation, wish me luck during exam time, wish me luck for results
And yeah, if you believe in god, please pray for me to do good..Atleast 26+ out of 40
Best of Luck Abhi
Is anyone here familiar with the laplace expansion of the determinant in terms of complimentary minors?
More specifically, how it applies to a special subet of 2Nx2N matrices
I have the role of deputy Director General, Supervisor and many other in my discord server, If anyone is interested in war, military, conflict and geopolitical stuff than contact me.\
Thank youuu!!
Could I get some help for question 6?
I’m not sure how to “ show” it :// thank you!!
x^2 - a^2 = (x-a)(x+a)
the equation will be (x-a)(x+a) / (x+a) it's equal to (x-a)
so the function is f(x) = x-a , a is any number in R except the -X
so the first derivative will always be 1
Ohhhh thank you so much @left knoll !
there is a formula
f^'(x)= f(x+h)-f(x)/h
apply this you will get your answer
nice
just want to make sure, in a problem like this i add 2 to every element in the vector of x? so it would be <4; 3; 4>?
or is it undefined because you can only add when the number of elements is the same?
mostly a vector is added to an vector only
I guess here we have to take the magnitude of the vector
You cannot add a vector and a scalar, as is shown in (e).
xbar, here, is a vector, and thus (e) would not be defined
yes, people do that sometimes
Yeahh I’m just a bit confused like… for the formula you can use it if your approach from right or left.. so I was wondering which one to use
Can anyone tell me how we got from Point A to Point B here? I feel like it's really simple but I'm blanking. It's part of a calculus 2 polar coordinates problem
Could someone go through how to differentiate these two questions step by step.. I keep getting confused with the square roots ahh
Thank you so much
It happens hhh
Hey guys. Do yall know how to draw logistics regression graphs on excel? Is that even possible?
@left knoll Does the asymptote x = -a exist for the f(x) -= x-a from that question?
@clever talon
not fully confident tho
Don't think so, As far as I know
Felt like it does
the denominator which is (x^2 + 3) will always be positive for all the values of x here,
so you need to solve for,
5-3x < 0
which turns to
x > 5/3
and given x< pie
therefore,
5/3 < x < pie
oh it is indeed correct,
I solved it this way too
hmmm, not sure to be honest
Does anyone know what is happening at the part that I circled?
I'm taking Calc 2 online at a community college so I basically have to teach myself
I don't understand why we are multiplying by 1 over cos(2theta)
He just used these rules
Cos(2x) = cos²x - sin²x
Sin(2x) = 2sin(x) cos(x)
To simplify the equation
After that he divided the numerator and the denominator by cos(2theta)
So cos(2theta)/cos(2theta) =1
And sin(2theta)/cos(2theta) = tan(2theta)
To simplify more
Ohhhh, makes sense. Thank you!
cot(π/3) = cos(π/3)/sin(π/3) = 1/√3
csc(π/3) = 1/sin(π/3) = 2/√3
cos(π/4) = 1/√2
(1/√3 + 2/√3)/(1/√2) = (3/√3)/(1/√2) = √3 * √2 = √6
thank you 🙂
Hello.
Someone know if is possible find the roots of a polynomial of degree N+2 having as only information a finite list of random points of said polynomial and knowing what is the degree of that polynomial?
With the mean being 18 and the SD being aprox 2.12. I dont understand the answer to d) if anyone can help
Because only 5! equals 5!, so 10-r =5
Thank you
Thank you but I was talking about 10-r
how does this work?
Since above is a dubblr profuct
(A-b)(a+b)
So you erase the a-b on top of botom
You can do the same with x and y to make itt easier
but if you multiply 2^x by 2^x isnt that gonna be 4^2x?
nah, it'd be 4^x.
a^x * a^y = a^(x + y) and not (a * a)^(x + y)
2^x * 2^x = 2^(x + x) = 2^(2x) = 4^(x)
ohh alright thanks
I kinda forget the basic probability so I'm not 100% sure of my answer 
thank youu, ive got a maths exam today so kinda cramming 
Meanq the derivative is equal to 0
So derive and find the zero points
@undone ledge
@weak lotus thank so smm
ain't it gonna be 4 x²
i put true for this since if Ax = 0 only has trivial solution then the vector components must be linearly independent, so A must span all of R^m but that was wrong, can someone please explain why
for 14. use the z-scores for 95% and 99% confidence then multiply them by Sx to find the respective +/- on mean
because Ax=0 has only the trivial solution, so the rank of A is n
Does anyone here know any resources for learning basic maths?
khan academy
2= log(4) (as base is 2)
then use properties of log
- means multiplication
" - "means division
then just solve normal equation
first find the derivative of the function and set derivative equal to zero and solve for x. to find the corresponding coordinates, plug those x values back into the original function and u will get the coordinates
Tyyy!!
who has a decent understanding at statistics here?
i don't understand at all how they calculated the mean and the variance
it doesn't make sense
btw opportunity = probability (bad translation lol)
standard deviation is if im not mistaken probably calculated here as a square root of variance probably
Anybody please recommend me some good books to study pure mathematics
I’m currently preparing for jee but wanna study higher mathematics too
Thank you so much
if you are new to pure math definitely do not start with a lot of those books unless you have a solid foundation.
Spivaks calculus is good if you’re looking for a more rigorous introduction to calculus/ an introduction to analysis.
how to prove it is also nice if you’re new to proofs
Okay I’ll try them first
Otherwise many of those books are very advanced
looks like a chatgpt copy and paste tbh which i see a good amount of people doing 😂
I think I have basic foundation
Thought so
can someone help me with this one? it is from the Essential Linear Algebra with Applications, by Titu Andrescu
Can someone help me with the third one? Basic trigonometry
hello, can somone help me with this problem: Find all two-digit natural numbers with the following property: When you add the number to the sum of its digits, you get 62.
Hint: If the number is in the form xy, then xy + x + y = 62.
I have tried and I cannot find a number like this. Is this even solvable or is the answer actually that a number like this doesnt exist? thank u!
Hmm
Oops
Let the number be 10x+y
10x+y+x+y=62
Hmmmmmm
11x+2y=62
If u put x=4, then
Y=9
So the number is 49
@floral marlin
thank u!
Np
Oot but the handwriting is so beautiful ❤️
ty :D
Want study math together? My favourite book is called "Introduction To Real Analysis" by G.Bartle , i really like it
Yeaa sure
Dm me
Integration by substitution
From blue pen down, 1st line is from the solution, we're given u=x^1/2 as a sub. 2nd & 3rd line is me trying it, where did it go south?
f(av) = af(v) <=> f(v) + f(w) != f(v + w), try checking out euclidean distance f(x,y) = |x - y|
let f(x,y) = |x - y| , then
|x1 - y1| + |x2 - y2| != |(x1 + x2) - (y1 + y2)|
tho in that case
|x - y| would mean the distance between the coordinates x and y as real numbers
not a distance of vectors v = (x1,y1), w = (x2,y2)
uh i don't know calculus so i prob have more questions than answers
but for what function did you substitute?
because i see two functions there
f(x) = 1/x and g(x) = sqrt(3x - 2x^2)
if you want to substitute for g(x) then you need it's derivative out in the integral right?
is that where you get sqrt(2) from???
kinda confusing
unless it's like 1/x composed with sqrt(x) whose overall composition is then composed with 3x - 2x^2
but that makes me even more confused
also another thing is
what i noticed
3x - 2x^2 = 2(3/2x - x^2)
3x - 2x^2 != 2(3/2 - x^2)
Since you did sqrt(2(3/2x - x^2)) then use sqrt(ab) = sqrt(a)sqrt(b) to pull out 2 out
you got sqrt(2)
But where the x at???????
😕
I'm supposed to be getting it into this form (a is an integer)
also can you tell me which line you're talking about :'D?
sqrt(3/2 - u^2)
Shouldn't it be sqrt(3/2u - u^2)
Like where the u at
it disappeared
????
is it the last line?
I dont which line idk how you count them
Its the first line below "FROM SOLUTIONS"
if that helps
yes it does, that 1st line below "FROM SOLUTIONS" is copied from the lecturer's solutions. I dunno how he got there
I keep getting a different answer
Are you sure he didn't forget to put 3/2u ?
Look
Sqrt(3x - 2x^2)
You pull out 2
Sqrt(2(3/2x - x^2))
You get Sqrt(2)Sqrt(3/2x - x^2)
but then he somehow subs
And gets Sqrt(2)Sqrt(3/2 - u^2)
Shouldn't it be Sqrt(2)Sqrt(3/2u - u^2) ???????????
for the form we have to use i think that 3/2u represents "a" which has to be an integer,, which is why u needs to disappear. But idk how it happened
yours is right but i still need to get it in the form
Well it would make sense , but i don't see how that substitution he made just magically makes u disappear on the left
Oh wait
Unless
@prime minnow i got idea maybe
OOH
what if he pulled out x too
sqrt(3x - 2x^2) = sqrt(2x(3/2 - x))
But like
