#help-43
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if I have
d = a, and 1 + d^2 = b, what's the relation between a and b
just put the values and find it?
by the way, assume a and b are given
if you want, you can rearrange it to
b = 1 + a^2
or
a = sqrt(b-1)
!noans
The purpose of this server is to help you learn, not to hand out answers. Do not ask someone to give you the answer directly.
!xy
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
is this directed at me
yes
, well im not the one asking the question
"not to hand out answers."
That command is !nosols
thnku
the answer was one step away for this question so i don't know what else i could have done
i mean ya 💀
@keen glacier Has your question been resolved?
wait a bit
im giving the entire question
so the way it looks right now is that the relation b = 1 + a^2 does not hold. b is 17/4, and a is 1, right? so what I wanna scale the expression and get all possible values of d where the relation holds (answer is d = 4, and d = 1/4)
how should I scale the expression?
what are a and b here
b is 17/4, and a is 1
i don't see how changing c and d would affect that
I wanna scale the expression up and down so that b = 1 + a^2 holds true
what equation do I use
Thanks
@keen glacier Has your question been resolved?
so according to the expression above, d^2 + 1 = 17/4, but at the same time, d = 1, which doesn't make any sense
I don't wanna use A. I wanna know to scale this to get the correct relation. The answer is scale it by 4 and 1/4
but how did they get 4 and 1/4
is there an easy way to know
u probably comparing coeffs and consists right?
but wait a second
yes
i wanna scale the expression by some factor so that the relation b = 1 + a^2 holds true, b in the case above ^^ is 17/4, a is 1
is there some equation I can use to get the scaling factor
a (17/4) is a constant of lower left expression and b is a coefficient of lower left exp
correct?
yes
ahh
what
ah
ahh
it's 4 or 1/4, but how can I get this from scratch
is there some equation that can give me this?
this
umm
what are you stuck on
if u multiply it by 4 top and bottom for example, it would give u a = 4, b = 17, b = 1+4^2 = 17
how did they get 4? that's where im confused
i definitely can't just guess it
$\frac{X}{Y}=\frac{x}{y} \iff X=AY and Y=Ay$
へいほー
you know
what's this
Expressions about fractions
by using Y=Ay, in this case, we get 17/4-(z+z^(-1)) = A(1+d^2-d(z+z^(-1))).
and
I want b = 1 + a^2 to hold, my a is the coefficient and my b is the constant
how can we write a simple equation
that checks for when b = 1 + a^2 hold
and what factor to multiply C(z) by
yh
what's the equation u derived?
as this equivalence transformation implies, when considering the equality of fractions, you have to consider the ratio A.
what's X, Y, x, y, and A
Ok so here what do we have
so in this case, 17/4-(z+z^(-1)) not always eq to 1+d^2-d(z+z^(-1))
Yes. Here, it's not equal. I want it to be equal.
since we want the fractional equation to be an identity, we use the Y=Ay (or BY=y) relationship we just discussed, and make Y=Ay an identity accordingly.
Y = 17/4-(z+z^(-1) , y = 1+d^2-d(z+z^(-1)), A is some const.
can u write it in latex
へいほー
just comparing these
upper left is X, lower left is Y, upper right is x, and lower right is y
ok what are X and x
へいほー
for this question, there is no need to think too much about X and x.
as i said, Y=Ay.
wait i use BY=y instead sry. B is also some const
so
$B\left(\frac{17}{4}-(z+z^{-1})\right)=1+d^2-d(z+z^{-1})$
へいほー
by comparing const (B×17/4 = 1+d^2) and coeff (B = d)
we get
$\frac{17}{4} B = 1+B^2\ \iff (4B-1)(B-4)=0\ \iff B=4 \quad or \quad 1/4$
nice
へいほー
and d is just B right?
yeah
how did u figure this out
just equivalence transformation
equivalence transformation is the essence of math
like this
so in my original C(z), the denominator did not equal 1 - dz - dz^-1 + d^2, right
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Integrate 1/(x-a)(b-x) where b>x
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What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
I got a diff ans from whats given
I used cts
(x-a)+(b-x)
And applied dx/root of 2-x2
partial fractions are probably your friend here
No no
Yea

Substitution
I used cts
Umm
I think the sub was something like acos^2 theta + bsin^2 theta
This typa sub is very weird
There is an easier
I doubt he would be able to guess it
Its just a 1/root quad
Wha
Hmmm
What is cts first off
Completing the square
yeah that checks out
why would you ask if you knew the soln tho
No i got diff ans
!show
Show your work, and if possible, explain where you are stuck.
Showing work is not possible
But i can tell u my ans
Sin inverse of (2x-a-b/a-b) is what i got
Ans is 2 sin inverse of root of x-a/b-a
Basically how do i change my ans to given ans
Think u did some calc mistake somewhere
Bruh
Are u 12th or?
12th
Helper can be at any grade xd
So whats wrong with the work?
Ye i meant hes on a another lvl when compared to me
Its rd sharma tho
Well i spotted minor errors but not the whole ans
Lemme check rq
Umm
They used u sub
Subbed x-a as u^2
So by cts is my ans right?
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Just complete the square
I aint preparing for jee
This is rd sharma not ncert
Rd sharma is ncert level😔
Les quit talking and how abt u help me
Uhhh
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hi
Problem: Simplify $\frac{\dbinom{200}{75}}{\dbinom{200}{74}}.$
7
I tried rewriting the expression using pascal's identity
so (199 choose 75 + 199 choose 74)/(199 choose 74 + 199 choose 73)
and then made it equal to x
and then i multiplied and distributed
so 199 choose 75 + 199 choose 74 = (199 choose 74)x + (199 choose 73)x
i dont know what to do next pls help
however, i notice that the denominator 200 choose 74 is equal to 199 choose 75 - 199 choose 73
<@&286206848099549185>
if you want to evaluate this, just use the definition of the binomial coefficient?
how
write it out. you will get a fraction of fractions with a bunch of factorials canceling out
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Can sb give me some ideas, thank you
nah wdym, totally legit!!
Maybe consider the determinant as a function of the diagonal entries. It's a pretty nice form.
Then, you can by a proof by contradiction, assuming all ways give a singular matrix and deduce that the coefficients of this function are all 0. However, also calculate one of the coefficients and deduce a contradiction.
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I think you can do induction. First consider replacing all diagonal entries with 0. Think about what is implied about the products in the determinant of the original matrix if the resultant matrix is still not invertible. Then try having the first diagonal entry as 1 and others as 0
quite similar ig
@civic glade Has your question been resolved?
Thank u so much, I'll try again
@civic glade Has your question been resolved?
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Any progress?
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A nine digit number is formed by writing all the numbers from 1 - 9 in random order. What is the probability that the number formed is exactly divisible by 4
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What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
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5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
!nogpt
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chat gpt gave me a different answer
!nogpt
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chatgpt is pretty bad at questions like these
Im just saying for reference
dont trust gpt for shit, dont even look at its answer
i wouldnt trust it
the fact it didnt match yours doesnt mean SHIT
show your answer and your work
actually if you just ask it the same thing again youll probably get a different answer from chatgpt
ik
theres this one JEE question that I tried to ask chatgpt atleast 10 times but got different (wrong) answer every single time until I used deep research
I realized
16 / 9! is wrong for various reasons
the answer that I currently have is 16/81
so
to help u understand.
your numerator is correct but your denom is not
I realized that the last number must be even for it to be divisible by 4, so there are 4 possible even numbers
there are 16 pairs of digits you could have at the end of your number to make it divisible by 4.
you counted them
[odd]2, [even]4, [odd]6 and [even]8
For every possible even number I have listed the number of possible preceding even numbers in brackets
I hope that makes sense
the total number of two-digit endings is not 9! nor 81 but 9 * 8
for which it is divisble
which is what you should have in the denominator
yo
2/9
wait that was the first answer i got...
how'd i get the first time?
ohhh yeahh
i remember
but i think thats wrong, lemme check
2/9 is the answer I initially got when I only took preceding numbers to be even but I believe that is wrong because the preceding numbers don't necesarily have to be even
dont confuse "number" with "digit"
ok by preceding number what I mean is the digit in 10's place
I think its 16/81
The factor that determines where the number is divisible by 4 or not is the last two digits Correct?
should i repeat myself
yes pls
yes correct. your denom is still wrong.
the total number of two-digit endings is not 9! nor 81 but 9 * 8
which is what you should have in the denominator
yes i said 9*8
cool
OH
9 choices for the units digit
two digit endings
Ohh
right
OHHH
WAIT
I GET IT NOW
AHH I TOTALLY forgot that
the chance of the fi rst digit being what you want is 1/9 but the chance 2nd digit being what you want is 1/8 since you have one less number to worry about now
ah, thanks
Im in 11th and I have a maths competetion to attend next month with 12th's portions so im cooked
anyway thx for ur help
Heyyy, I'm also 11th grade and will have a math competition test XD
which country u from
Not next mouthn tho
I'm Vietnamese xd
cool
im indian
i suck at permutation combination and matrices
those topics haven't been taught to us but i've tried to learn it on my own and i failed
I've been able to learn integration, complex numbers and stuff
Dude, no offense but there are so many Indian in this server
lol
why would I be offended at that
tbh you could tell me india is trash country and i still wouldn't be offended unless u racist or smth
Indian are really good at math i guess
not rlly
its a misconception
My competition focus on solid geometry and differential
half the people in my class lack skills in maths
like we are learning how to add and subtract complex numbers and the dudes beside me are failing basic addition subtraction 🌚
🌚
In fact I'm not taught Matrices and complex numbers in high school
He’s not talking about the general public
matrices will be taught next year
He’s talking abt peeps doing olys and stuff
right, in that case, yes, indians are very good at maths
tbh every country has that though
i think the reason we got good people at that is cuz of our absurd population
Not when you compare the populace of people like them
true
Oh yeah, that makes sense
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Anyone knows why this is correct only when b=1 but for all n multiple of 2 and all a
Problem is if b is 0 the whole thing is 0 but it shouldn't be
Idk if i have forgotten something st the roots at the start
Cause i cant see a step thats not correct thats why im surprised how i got wrong result
this is only useful to your partial fraction decomposition when b is not zero
when b = 0, I is trivial
Ok
But
Even when b isnt 0 for some reason there is a mistake
In these steps
Idk where though
Assume b=/0
try writing the solutions for n=3 and n=4 and see where your assumptions break down
It doesnt
Oh wait wdym
This solution is for n multiples of 2
Thats how i defined the problem
what does "b = 1 but for all n multiple of 2" mean
For n odd i cant write sum of n/2 +1 terms
Like if i use any multiple of 2 for n
Or any number for a
Its correct
This was the goal
But i also wanted it to be true for any b
Be its only true for b=1
what does "any multiple of 2 for n" mean
Like {2,4,6,8....
Yes sorry forgot name in English
For any positive even number
n
And for any real number a
But b=1 otherwise it fails
But it shouldn't since steps seem correct idk why it does
I forgot something somewhere and cant find now
yes you assumed n was even here
for n=3, you should write out the 3rd roots of unity to see which term you're missing
Yes ik
That's not an issue
Thats assumtpion at the start of the problem
So n is even positive, a is real and b is positive
The issue is that the end result only holds for b=1 and no other positive number

Idk why that is
Idk why you focusing on n leav n
b is the one that needs fixing
Somewhere there needs to be an extra or less or many b terms in that expression
it's in your first message
just answering your quesiton
Just focus on it now that you understand what i wanna find
lmao
Since assumption at beginning was n even positive a real and b posutive end result should be correct for those assumptions
But its only for b=1
So there is a mistake or many in one or more steps
Thats what im looking for
no really it's not clear
you haven't demonstrated why your expression is wrong for b not equal to 1
Because desmos says so
I would assume its accurate
So by comparison its wrong
If end result is wrong there is a step in the solution that has a mistake
I put my result
And d/dx in the front
Then a/(x^n +b)
When moving a,n no problem
When moving b problem
Ive checked it many times id assume i didnt miss type something all those times and got the same wrong result
Anyone?
@rose goblet Has your question been resolved?
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,,\int (x-3),\sqrt{x^2+3x-18},dx
!
!show
Show your work, and if possible, explain where you are stuck.
Is this right?
Hint: U sub
WAIT no, I thought I saw a fraction there, mb
Oh k
First term looks good
I presume you used arcsinh for the rest of it
Just check with WA
Uuh no
,w integrate (x-3)sqrt(x^2+3x-18)
I think there needs to be 729/16
So that's fucked
They have it
Bruh what method is that
Just didn't distribute everything
;(
I meant for the attempt in the photo
Yeah
^
11
My eyes have been permanentely bleached
I cannot with these equivalent forms
I know what WA did and I hate it
Lemme crosscheck
,w is 1/3(x^2+3x-18)-9/2((2x+3)/4)=1/24(8x^2-30x-225)
Yeah it might be wrong
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yo quick question can this be done
nop
log is undefined for negative x, so depends what tools you've been taught
oh yea it was negative..
this the full question
Yeah but ln(-5) doesn’t exists
i dont know what course this is so the methods they may use might be different but the natural log function is undefined for values less than or equal to zero, so the question is nonsensical unless they actually want you to go to the complex world
yh im just goin to leave it i have no clue like ive been asking AI and it tells me that the integral is undefined
Yes for this reason
,calc log(-0.5)
Result:
-0.69314718055995 + 3.1415926535898i
Complex world 😱
woa
so basically
alr
the domain doesnt support
it does NOT stay defined on [-1,0]
so yeah thats a bitchass integral
Closed by @cyan lava
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why is it for unit circle we alwayrs write (sinx,cosy)
using pythagorean theorem on the unit circle
huh
bad notation.
you mean x = cos(theta) and y = sin(theta) yes?
not the same thing
(costheta,sintheta)
this is convention.
the idea behind the unit circle is that the zero point for your angle is (1, 0).
huh?
and theta increases counterclockwise.
yea
i don't think there is really a sacred meaning to why this starting point and direction was chosen.
rather than e.g. (0, 1) and clockwise.
wdym "use it in radians"
like if you ahve it in radians and need to find a point
like between for a b or c
and do it instead of having to convert
i have no idea what you're talking about.
are you looking at a problem right now?
cause i really legitimately cannot understand what "have it in radians" or "between for a, b or c" means!
like this
ok right so you want to be able to tell which quadrant an angle lies in when it's given in radians.
yes
a full circle is 2pi, so a quarter of it is pi/2.
and not have to convert
the breaking points between the quadrants are 0, pi/2, pi, 3pi/2, 2pi, ...
(which are just 0*pi/2, 1*pi/2, 2*pi/2 and 3*pi/2)
compare your angle (11pi/6 in this case) against each one of these in turn
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yes, 11pi/6 > 3pi/2
.close
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if you want to ask something then spit it out...
what's with this close-reopen cycling
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how does one find the answer for bii) I tried and got pi/3 but the answer says it’s 5pi/3
Just look at the elements of the matrix and find the theta that works
You haven't shown enough work to know what you are doing
You can see that B is in the third quadrant
wait no
its not -1/2 tho
I'm talking about column 1 of B
You can use column 1 of AB instead if you want, it's the same thing
I don’t get it
Can you see that B is a rotation matrix
yes
The first column is cos(theta) = -sqrt(3)/2, sin(theta) = -1/2.
Using CAST, cos and sin are both negative in the third quadrant
So look it up on the unit circle and you see that theta = 7pi/6
Then A rotates it a further pi/2 so you get 7pi/6 + pi/2 = 7pi/6 + 3pi/6 = 10pi/6 = 5pi/3
Alternatively, you look at column 1 of the matrix AB, cos(theta) = 1/2, sin(theta) = -sqrt(3)/2, cos is positive and sin is negative in the 4th quadrant, and you again get 5pi/3.
okay I understand the answer I just got it now
but I didn’t learn about using the cast stuff from where I got my notes for this
could u explain the general like solution? like when ur talking about the columns of the matrices
CAST is just expected knowledge by the time you are learning this
well yeah I know CAST but I didn’t know I had to apply it to this question like that
There is nothing special about the first column, it's just the entries of a rotation matrix has in its entries cos, sin and -sin
Column 1 just happens to have cos and sin in it, and adding -sin to your system of equations doesn't give you any extra information
wait I think I’m getting it now
For the matrix AB you are just solving the system of equations:
cos(x) = 1/2
sin(x) = -sqrt(3)/2
cos(x) = 1/2
-sin(x) = sqrt(3)/2
The first two equations are from column 1 and the second equations are from column 2
Hopefully it should be obvious that equation 3 and 4 don't help
Yeah yeah
so instead of just setting the anticlockwise rotation matrix equal to the matrix AB and getting cos(a) = 1/2 which would imply a=pi/3
I use the CAST thing instead to get it
You don't really need that CAST rule, it is just a helpful sanity check
well in general then
Your problem, maybe, is that cos(pi/3) and cos(5pi/3) are the same value.
and things like CAST help you set up basic expectations for what you think the answer should look like and helps you reduce the chance of an error, but it isn't strictly necessary
^
so what ur saying is I don’t have to use the cast diagram?
I mean now that u ahve explained it it seems pretty simple
use it for sin and cos, the answer that appears in both sin and cos is the overall answer to the question
I am saying you don't have to use it, but it is good practice to use what you've already learned before to reduce your mistakes.
Solving math problems isn't about just never making an error, it is also about using what you've already learned so you can identify if you've made a mistake on your own.
I get that but
I don't know what is still unclear, we've went through a few different ways to solve it. Just pick the one that you think is easiest.
no no it’s not that
looking back on it now
I made the mistake of
sina = sqrt3 / 2
Instead of negative
and that’s what probably led me to make that mistake of pi/3
But nah I get it
u gave me the way to solve it and I understand what to do now
so thank you
and also what about C)
I have no clue
AB rotates by 5pi/3 radian any vector v from R^2 when you do ABv. what fraction of a full turn 2pi radian is that?
what 😀
hum maybe the geometric interpretation of what AB does is not a good rabbit hole for now
reading what was done before, AB is a rotation matrix with theta = 5pi/3. A with theta pi/2 and B with theta 7pi/6. the theta of AB is 7pi/6 + pi/2 = 5pi/3, the sum of the two
that’s true in general the product of rotation matrix is a rotation matrix with theta the sum of each
Now, if theta is a multiple of 2pi the rotation matrix = I
So the question asks when the smallest multiple of 5pi/3 will be a multiple of 2pi
it does..?
because (AB)^n will be a rotation matrix with theta n times 5pi/3
by the argument i just did
now you know though, the general reason/intuition why this works is that matrices represent linear transformation (functions) transforming the plane R^2 and multiplying them is like composing functions. that’s kinda what i was getting at but that might be too much now
if u wanna have a Quick Look through these…
It’s the matrices notes I used and I cannot find anything like that in there
https://www.youtube.com/watch?v=kYB8IZa5AuE&list=PLZHQObOWTQDPD3MizzM2xVFitgF8hE_ab&index=3 if you want to see this in action
Quite possibly the most important idea for understanding linear algebra.
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I’ll make sure to have a look, I also got a guy who does these topics for my curriculum which I will also have to look through but thanks for the help
✌🏼
you have 2 examples of this interpretation of the matrix product
but yeah i agree your question is tricky without this intuition. you would have to multiply (AB) by itself to see the pattern
perhaps
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can someone pls tell me how i wud turn this into partial fractions
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is the fraction supposed to be u/(u^2-1)^2 ?
i feel like factoring this into
4/[(u-1)^2 (u+1)^2] would make the partial fractions easier
and I think yk the case where some of the expressions reocurr
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@copper loom Has your question been resolved?
@copper loom Has your question been resolved?
Idk if this is true
But here's my proof
Assume Z(G) is not 1
Then there is some nonidentity element g in Z(G)
The conjugacy class of g is just the set with itself
Because it commutes with every element
But <g> is a subset of the conjugacy class
This implies g has degree 1 and is this equal to 1
A contradiction
This |G| = 1 + 3 + 3 + 3 + 5
Also on second thought
I don't think this problem is possible
Because a group of size 15 is always a cyclic group by the sylow theorems, so it must be abelian
But I think my previous proof is the intended solution
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are we allowed to use arctan(90 degrees) or no?
so basically can we use it for right angled triangles?
arctan is defined for all real numbers, but only returns a number between -pi/2 and pi/2, exclusively
if we expect outputs to be meaningful, we shouldn't feed degree measures into it; they should be like, lengths of line segments
can u dumb it down
but if you say that 1 degree = pi/180, then the answer is yes, arctan(pi/2) is a number. it just doesn't mean anything, probably.(?)
I dont understand half of the terms
tan is a function; it takes an angle measurement and outputs a real number, which you can think of as the length of a line segment. kind of.
arctan is the inverse of tan: it takes the length of a line segment (again, kind of) and returns an angle measurement
is 90 degrees the kind-of length of a line segment? sure, technically, if you specify that
90 degrees = 90 * (1 degree) = 90 * (pi/180) = pi/2
you probably meant tan(90 degrees). the answer to that is, no, it's undefined.
you can give it other angle measurements from your (right) triangle, just not 90 degrees
@wary mulch Has your question been resolved?
ohh
how will it be even undefined?
and also for this question i didnt round it to the nearest minute because the question didnt ask for but in the solution, it rounded up to the nearest minute
so im a bit confused
with that
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hello
on a right triangle, what's the "opposite" or "adjacent" side of the 90 degrees? both are adjacent to that angle
algebraically, tan(x) = sin(x)/cos(x). What is cos(x) at 90 degrees? Does this cause problems? (hint: yes)
do u meant to replace adjacent with hypnoteuse?
because the opposite of a right angle is hypotenuse
im referring to "adjacent" and "opposite" sides as you would for SOH CAH TOA, if you learned that
i.e. not the hypotenuse
if you had adjacent/hyp, that's just cos, and if you had opposite/hyp, that's just sin
true i understand now becuase if right angle was the subject, there would be only 1 oposite, therefore two adjacents
which cant be possible
i guess you can think of it that way too, but i hesitate to call the hypotenuse the opposite, cause it usually isn't
why isnt it?
well, because the angle is usually touching the hypotenuse and one other side, so the last side is the opposite, and it can't be the hypotenuse ofc
i think you're right and its ok to say that the opposite happens to be the hypotenuse. we are considering an undefined case, after all
but usually, A, O, and H are three different sides, so that's why i hesitate
i'll say
for this particular case
as for this, maybe they said "round all angles to the nearest minute" at the start? if not then ggs
jits not touching the hypotenus
e
im talking about this as the subject
u can see its opposite and also the hypotenuse
yeah yeah, and i meant that we "normally" talk about a or b, so i wasn't sure if we can just immediately say opposite = hypotenuse
but i think it works for this example, and doesn't cause any problems
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is the * misplaced in the ∂ψ*/∂t on the far right?
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"If g(f(x)) is injective, so is f(x)."
Can I prove this statement with something other than contradiction?
recite the definition of injectivity
If for some x1,x2 in domain of h(x), h(x1) = h(x2), then x1 = x2 for injectivity
So g o f is injective.
Any x1, x2 in dom(gof), gof(x1) = gof(x2) implies x1 = x2.
How do I continue from here? Shouldn't there also be some restriction on g
why?
Then how would I continue here
Didn't you already do that by typing x = y ?
what?
Also is this f the same f in question or some general f
there is an intemediary step which u have to fill in. we dont know that f is injective. that is what we are trying to show
same f
If f(x) = f(y)
Then g(f(x)) = g(f(y))
Then x = y
the end
Interesting

Ohhh understood
I had a question regarding this method that couldn't we just do this for any general f
Then i realised gof should also be injective
OK thanks
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hi, if im finding the gradient of a tangent parallel to the y axis, will the dy/dx value be undefined or will it = 0?
my dy/dx is a fraction, so im not sure whether i should equate the numerator or denominator to zero
thank you!
it's undefined
so i should equate the denominator to zero right?
sure why not
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how do i find the area
i don't get it intuitively how the area is being traced
at pi/6 the curve passes through origin again
so the part in the 1st quadrant must be traced when were moving from 0 to pi/6
but after pi/6 since r < 0 we get into the third quadrant
then until pi/2 we are in the 3rd quadrant
after pi/2 we get in 4th quadrant and finally at 5pi/6 we are at origin again
dumb
idk
i don't get how the area is being traced out
can someone help
i could figure how areas are traced before this problem
when solving those problems should i care about it ? how its traced
or just solve the integral find area and move on
i am not very used to checking answers and stuff am lazy
Kinda
U need it to set bounds of integration
yes
U can try graphing the major points
And try to visualize the thing
For example at pi/2
The line should be exactly along the y-axis
And at 3pi/2, the thing should also be along the y-axis
i kinda understand how its being traced
Then what is the issue 
yea we can do those things but they don't always help
for example in this problem its not enough
u can divide the area into 2 parts
or theres a better way
cuz symmetry
the area of one side = integral from area from 0 to pi/6 (the top) + area from 3pi/2 to 2pi - area from pi/6 to pi/2
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How the hell do I explain these kinds of questions
Last time I tried to explain this it took like 20 min
It's gonna take 1 page for me to write the explanation
Context
It's for 3rd and 4th graders
Math Olympiad
And I didn't even get it completely right
hmmm
Yeah I understand the explanation but it's just
though we do know D is either 1 or 2, and A is either 8 or 9
actually maybe A=9 is not possible cause B+E is at least 1 and we would have sum 9100 or higher for the first addition
its c
because a is either 8or 9
3rd and 4th grade
and d is either 1 or 2
If I wrote a is either 8 or 9 and see how it affects the addition is gonna atleast take up half or 75% of the page
nah
actually maybe A=9 is not possible cause B+E is at least 1 and we would have sum 9100 or higher for the first addition
you can find D next
then G then C
yeah ann is right

