#help-0
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np
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Simplify $\frac{bx(a^2x^2 + 2a^2y^2 + b^2y^2) + ay(a^2x^2 + 2 b^2x^2 + b^2y^2)}{bx + ay}$
Kepe
Hints only please.
Kepe
have you tried to do all the calculations before?
multiplying it out completely?
I thought about that but then again I didn't think that the author of this problem wants you to get into that complete mess
but I will try, alr
Special Factorizations, things like $a^3 - b^3 = (a - b)(a^2 + ab + b^2)$
Kepe
$$\frac{ba^2x^3 + 2a^2y^2bx + b^3y^2x + a^3x^2y + 2ayb^2x^2 + ayb^2y^3}{bx + ay}$$
Kepe
Have you thought about (bx+ay)
multiplied out
The parentheses are almost identical, yes, but the middle term isn't
ok so
Ive tried to do it but I'm not understanding. apparently I can not make anything
Have you tried like expanding only the insides of the two parentheses and see what happens?
the original term is
It's already expanded?
Or do you mean multiplying out
Oh ok
$$(a^2x^2 + a^2y^2 + a^2y^2 + b^2y^2)$$
$$a^2(x^2 + y^2) + y^2(a^2 + b^2)$$
Pluton
also the bx and ay
Maybe helpful when added with other expression
Now group all the bx terms and ay terms separate maybe?
Other parantheses factors like
$$x^2(a^2 + b^2) + b^2(x^2 + y^2)$$
Pluton
$$\frac{bx(a^2(x^2 + y^2) + y^2(a^2 + b^2)) + ay(x^2(a^2 + b^2) + b^2(x^2 + y^2))}{bx + ay}$$
Kepe
just
?
its already seperate?
When you multiplied have you tried swapping the middle terms?
wait, let me try
Like swap 2a^2y^2bx and 2ayb^2x^2 and then factor?
Now you can group
$$(a^2 + b^2)(ayx^2 +bxy^2) + (x^2 + y^2)(ayb^2 + bxa^2)$$
Maybe factor ab and xy
$$xy(a^2 + b^2)(ax + by) + ab(x^2 + y^2)(ax +by)$$
This is perfect
Pluton
Maybe
Not really but something could be factored again
$$(ax + by)(xy(a^2 + b^2) + ab(x^2 + y^2))$$
Pluton
This doesnt seem to help does it
Yesss I think this works, wait a sec
yes it worked, thank you
Swapping the terms seems to be how you solve this
thanks for your help too!
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What is the best way to deal with questions like these without having to spend an hour on writing three pages?
I trying to prove that the derrivative of this function will be 0 but it becomes an algebraic nightmare really fast
I used the chain rule
you don't need to differentiate anything here
twice per term
you can just combine the terms with log properties and then simplify
and then you are left with a constant
im nervous for an exam I will have soon, pretty sure I will make mistakes like these on it
and waste so much time on a wrong approach
happens. but you should probably sooner try to find a different approach
sure suffering through the math can work. but especially in exams the questions are rarely like that
well at least in good exams
always try a bit of different stuff around before you tunnel vision one approach
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i’m kinda dense and can’t do easy question
what does this say
Make those two equations equal to each other, then solve for x
just started learning calculus and was told to do it by differentiating and then equating something(teacher didn’t finish his sentence and zoom died)
but regardless
A(2, -4), B(-3, 6)
don’t really understand part B when it ask to find the vertical line through M meets the parabola
does it just mean it’s perpendicular to AB which M sits on? or just like a 90 degree line through M
,rotate
<@&286206848099549185>
To find the midpoint, average the coordinates of A and B. (-0.5,1). Then it says it’s a vertical line through m so it must go through x=0.5
i’m up to that already
so then i just substitute x = -0.5
to find the value of y at T
Into the equation of the parabola to find T
right , but then i’m confused about showing the tangent at T being parallel to AB
So you can find the gradient of AB. Do you know how to differentiate?
yeah
gradient of AB is given already
of -2
gradient of parabola at any point is 2x-1
oh nvm i’m a brick wall
i see now
🤦♂️
So differentiate equation of parabola and sub in value -0.5
so the equation of tangent is y=-2x+17/4
which has same gradient hence parallel
ty for the help
Yeah, best not to waste time finding whole equation though just finding gradient is -2 is sufficient.
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Can u plz plot this signal?
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is anyone able to walk me through this
What have you tried?
I actually have no idea where to start on this
do I need to use the division method or something to solve this?
Have you expanded the left hand side of the ODE using the product rule?
yes
or wait no I was wondering when I do that do i need to treat y' differently than a normal variable
Uh no ig?
Product rule the LHS, then just plug and chug Y(x) and use the fact that y(x) is a solution
right so I have this on the leftside right?
What happened to the x^2 on your left term
ΣAC
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How does this happen like what are the more in depth steps
The way i tried to do it was by just getting rid of a^4
difference of two squares
They factored a^2
wait
Like Why couldnt i do this ?
No?
yeah factor out a^2
Better question. Why could you
Jesus f. Christ
Arent divisions for algebra things like this where for the powers you can substract them
No
a^4/a^4 is a^0 so nothing ?
Pluton
When we do this normally we get 4/5 which is 0.8
right
When we do the illegall thing of cancelling 3s we get 0.5
So then i need to factor out a^2 which means?
How to factorise some basic expressions! Thanks for watching. (Also called factoring or factorizing in the US).
Expanding brackets: https://youtu.be/63oU-AIzTcE
Simplifying expressions: https://youtu.be/yigRz8b9eL0
Factorising quadratics: https://www.youtube.com/watch?v=1aq6N9wzP8s
Algebra - Beginner to Master playlist - https://youtube.com/...
Yes
And i can cancel out a^2 now because they are multiplying not an addition
Yes
guys sorry butt....
Does anyone have a Chegg acc
Like I'm in urgent need for it rn
Why would you ask that in math help channel?
so say this problem came up i could also do this
Yes
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Because I'm exhausted from getting NOs from other servers
but I literally need help
Like fr fr
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omfg no one believes me i have no idea why
What do you want
What are you talking about
‘Believes you’
No idea why someone could be in urgent need of a chegg account, you can’t just get help?
I'm just tired of people saying no when they have an account and don't want to help because they think I'm gonna rob them or something lol
Idk wanna help ?
Nobody’s obligated to give you their account
I don't need the acc
Just post what you’re stuck with and people will help if they wish
just want them to search for the question on Chegg
Either way they’re not obliged too
dude srsly
It is still giving you access to it anyway
omfg
I'm not trying to get attention
omg no
I literally need a Chegg account, it doesn't matter if this is a math help server
but I apologize for seeking help ig lol
Could have posted the question
Could have gone to a physics server
A chegg server
But noooo
Alright thx
To perform calibration measurements, the researchers need to rotate the telescope by 90 degrees. For that, they fire the MRE-1 thrusters at the bottom edge of the primary mirror (see figure)
for 0.5 seconds with a thrust of 2.5 newtons.
This question is considered to be an advanced question
It's related to rotational motion and thrust force
Right well sounds like the figure’s important
And go to #old-network
There’s a physics server
@magic plank Has your question been resolved?
How long does it take for them to respond ?
Depends
because it has been 15 minutes since I posted the question
On the question, time
ok can't U solve the question ?
Also if you reference a figure you should post the figure
oh my bad
You also haven’t actually asked any questions
You’ve just made statements, so nobody will really be able to solve anything
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There's a formula for binomial expansion of powers which aren't positive integers (re. expanding surds):
(In this case, replace "x" with "3/x" everywhere, and set n=1/2)
is it different to the normal binomial theoreM?
If something like this one is the one you're used to, then yes: this pictured one only holds for natural powers but can be used to expand any value of a and b, the previous one can be used for any power of your choice but (unless n is natural) you have to restrict your choice of "x"
@celest perch Has your question been resolved?
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.reopen
someone pls help me
converting (cos2x + 1) into single angles would be the first thing you should do
use these
@peak tiger Has your question been resolved?
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why is the double derivative: $\frac{d^2y}{dx^2}$, is it just notation
azorfus
like, when you do this: $\frac{d}{dx} \frac{dy}{dx}$
azorfus
shouldn't it be$\frac{d^2}{d^2x^2} y$
azorfus
It's just notation

It was just a link I found, but it's mostly notation
what is L
Nice, like how newton used dots over his stuff
Sure
nice
btw, to study partial differential equations, how good should you be at "normal" calculus
There's no good way to answer this. Just as good as possible
so jumping over to PDE's just after starting calculus mustn't be a good idea
No way to know. Answer depends on you and your situation
You definitely need a good grasp on differential calculus and integral calculus first before differential equations
oh
whats the difference between differential calculus and equations
stuff on google explaining this difference is confusing
Like sin(pi)=-1 is an equation
Idk why but that was the same question i asked my teacher yesterday 🥲
But understood nothing
But it doesn't have a derivative
lol
oh
d/dx sin(x) = cos(x) is an equation AND had a derivative
so all differential calculus stuff with equations are differential equations
i see, "had"?
Differential calculus is calc 1 or derivative calculus
oh
It's just a naming scheme, where differential calculus is calc 1, integral calculus is calc 2, vector calculus is calc 3, and differential equations is calc 4
Real analysis calc 5-7
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oh
interesting
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in this example of a real world usage of square roots, what's the purpose of the -1 in the equation? like, why is it there, its not explained from what I can tell
the equation is best rearranged as $V_2 = V_0(1+R)^2$
Ann
(value at 2 years) = (starting value) * (1 + rate)^2
it is from this equation, with some algebra, that you get to $R = \sqrt{\frac{V_2}{V_0}} - 1$.
Ann
@alpine sable does this make sense to you?
should i explain exactly what's going on algebra-wise?
yeah thatd be great
ok well first off does the equation $V_2 = V_0(1+R)^2$ make sense to you?
Ann
just to make sure that we're on the same page on that front
i dont see why its (value at 2 years) = (starting value) * (1 + rate)^2 instead of (value at 2 years) = (starting value) * (rate)^2
im unsure what the 1 signifies
well let's try a concrete example shall we
let's say that you have an investment worth $1,000 that appreciates by 5% every year
can you tell me what its value will be after 2 years?
1100, right
no
you're close but not quite
let's do it year by year
in the first year, the investment grows by 5% of its value. it goes from 1000 to 1000 + (1000 * 0.05), or 1000 * 1.05.
does that make sense to you?
yeah
ok
so you see that an appreciation by 5% is actually a multiplicative increase rather than an additive one as might appear initially
and specifically it is a multiplication by 1.05
or (1+R) generally
you can think of the 1 as standing for the principal and R as standing for the interest (or appreciation or gain or whatever other term is more appropriate i guess)
yeah that does make sense
in the second year it'll be the same thing, and the value will multiply by 1.05 again
thus getting us 1.05^2
,calc 1000 * 1.05^2
Result:
1102.5
$1,102.50
of course, the $2.50 difference may seem small, but so was the initial investment (in finance terms anyway)
notice that if you had just multiplied by the rate squared, you'd get this:
,calc 1000 * 0.05^2
Result:
2.5
and your thousand dollars would've devolved into chump change
@alpine sable does the formula $V_2 = V_0(1+R)^2$ make sense to you now?
Ann
im still thinking this through, but im think im getting it
ping me when you're ready to move on to solving this equation for R
@alpine sable Has your question been resolved?
oh i think i get it
the interest is a percent of 100 (of course) and since 100% = 1, the 1 symbolizes the initial value of the investment
the sell value = the initial value * (the initial value + the gain) squared, which is 1 * whatever percentage
i think im on track
okay yeah sorry for the delay on my part
was busy doing irl things
so now the algebra that i promised
no worries
start with the equation: $$V_2 = V_0(1+R)^2$$ divide both sides by $V_0$ to get: $$\frac{V_2}{V_0} = (1+R)^2$$ square-root both sides to get: $$\sqrt{\frac{V_2}{V_0}} = 1 + R$$ and finally subtract 1 from both sides to get $$R = \sqrt{\frac{V_2}{V_0}} - 1$$
Ann
also while im at it
you can do similar things with periods other than 2 years
you would just take roots of other degrees (cube root, 4th root, etc.) depending on how long the time is
thanks, ill experiment with those rn, itd be a good way to retain this logic
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guys I forgot how to read as English (it's set theory)
the set of all x in D such that the predicate P holds for x
might reword the last bit depending on what P is
that was perfect answer!!!
I just couldn't remember 'such that'
sometimes also see "where P of x is true"
thank you!
yw
If you’re done then .close 🙂
sure! one more question!
how to close? I confuse little bit 😄
Just type .close
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how do I differentiate this?
f(x) = 1 / (3x - 1)
gimme steps on how to do it
I dont know how to get the (3x - 1) to be differentiated
Do you know how to differentiate composition of functions $f \circ g (x)$ ?
Twenty
Okay so the formula is $(F \circ g)' = g' \times F' \circ g$
Well here we already have a f so
Twenty
Can you express f(x) = 1 / (3x - 1) as a composition of functions ?
no i guess
I think you might be overcomplicating it. Maybe they just know the power chain rule so far
what is that?
\frac{d y}{d x}=\frac{v \frac{d u}{d x}-u \frac{d v}{d x}}{v^{2}}
$$\frac{d y}{d x}=\frac{v \frac{d u}{d x}-u \frac{d v}{d x}}{v^{2}}$$
||𝓚𝓪𝓼𝓹𝓮𝓻||
I meant for this one
Fog
oops
what have you learnt
this one
like what do you know
whats that one
I dont get the composistion function
when you differentiate x^2, the power thing goes down
you are not required to use this tbh
this one
this one so far
like how about we start over @umbral girder
ok
cause I feel that you are confused
just delete your recent memory
f(x) = 1 / (3x - 1)
you try and find f'(x)
right?
yes
did you learn Quotient rule
Im not familier with the terms so probably nope
I learned derivative in general
right
this?
uhh
this one actually
Math explained in easy language, plus puzzles, games, quizzes, worksheets and a forum. For K-12 kids, teachers and parents.
the one here
I dont know most of the terms there
owh ok then
yeah
those are variables?
yeah
what variebles to be precise tho?
,tex for $y=\frac{u}{v}$
||𝓚𝓪𝓼𝓹𝓮𝓻||
,tex then $\frac{dy}{dx} = \frac{\frac{du}{dx} v -\frac{dv}{dx}u}{v^2}$
||𝓚𝓪𝓼𝓹𝓮𝓻||
yeah
I was just confused with the formula since I never used it
actually I should just give the whole question
yeah sure
for your info tho, I was never taught of the formula, I was just went by and do the differentiation directly without using any formula
$$f(x) = x^y$$
$$f'(x) = y(x)^{y-1}$$
MarveI
you only know this?
I was only taught of the rules of how does it work so yea I dont understand the formula thingy, but ye now I know
ye thats the formula in general
the problem was that on how to apply it on a fraction
right then, now I dont know how the function gets determined here
do you need calculus for this?
I mean like it is rigorous
but you can also solve it graphically
maybe try dividing into two parts
1/(3x+2) and x^2
btw is this true?
decresing = negative
increasing = positive
for the determining the function
and find it they are increasing/decreasing functions
welp I havent learned power chain rule
but I already solve for that
but this one
it is not increasing nor decreasing
this one true right?
maybe better way
when x increases, y increases -> increasing and vise versa
f(x) = 1 / (3x + 2) + x^2
f(x) = (3x + 2)^-1 + x^2
f'(x) = (-1)(3x + 2)^-2 (3) + 2x
f'(x) = [(-3) / (3x + 2)^2 ] + 2x
@carmine oar
[(-3) / (3 (-) + 2)^2 ] + 2 (-) --> (+) output + 2 (-), (+) + (-) = (-), so function is decreasing
this correct yes?
$\left(\frac{f}{g}\right)'=\frac{f'g-fg'}{g^2}$
Categorist
whats this?
quotient rule
owh, welp thats just the same as this then
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?
@alpine sable Has your question been resolved?
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yo, can someone help me with this qn? ive defined the basis step but i have no clue how to even start on the inductive step
For all n, let P(n) denote if n can be written as a sum of distinct non-negative integer powers of 2.
Basis step:
P(1): 1 = 2^0
Hence, the basis step is true.
Inductive step:
Assume P(1)...P(k) is true
k + 1 would be either odd or even.
Case 1: k + 1 is odd
Then k is even
The representation of k would be 2^p + ..., where p ∈ ℕ.
This is because the inclusion of 2^0 would cause k to be odd.
So, we add 2^0 to k to obtain k + 1.
Case 2: k + 1 is even
I think you have your cases confused
oh right
okay done
problem is i have no idea how to get from k => k + 1 if k + 1 is even
Alright so you know that this is binary right?
Oh really, alright so it could be a good idea just to experiment with that case using binary strings, which could give you an idea of how the transformation should take shape
i see, how do i "experiment" tho?
like do i just keep trying diff values and combinations?
Yeah just go from 1 to 2, 5 to 6, 31 to 32, 75 to 76 and so on
i see, then there should be a noticable pattern rite?
from there then ill come up with the proof
okay thanks alot sir
Yea sort of, it’s different from the odd case though
Yeah np
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can someone explain to me why the -1 is still there in the expression even after being multiplied?
shouldn't it just go away since it's already been multiplied?
wdym
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<@&286206848099549185>
@alpine sable Has your question been resolved?
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The selector of the Serbian national football team made a list of 27 players for the World
Championship: 4 goalkeepers, 9 defensive players, 11 midfielders and 3 strikers.
(a) If the selector has decided that the goalkeeper will be Stojković, in how many ways can he choose
the other 10 players for the match against Switzerland (regardless of their position, but that they are not
goalkeepers)?
(b) In how many ways can he choose 1 goalkeeper, 4 defenders, 5 midfielders and 1
a striker who will play in the match against Brazil?
for the a
I did 23 choose 10
because it said their position didn't matter
and all players except goalkeepers is 23
is this right?
for the b
i don't understand whether it is permutation or combination
also sometimes when i do combinations i do them in different ways but they are both correct
if someone could just help me tell the difference i would greatly appreciate it
<@&286206848099549185>
@shy jackal Has your question been resolved?
yes
how many ways can you pick 1 person out of 4 people (for goalkeeper)
4
how many ways can you pick 4 defenders out of 9 defenders?
9x8x7x6?
11x10x9x8x7
multiply
but why it isn't it combination
for example
5 middlefielders out of 11
it says nowhere there is a difference between
left middlefielder and right
true
so it could be either way
does the order that you pick the players matter?
i don't know. Maybe yes because they are not all equal
like goalkeeper is different from striker
wait
can i ask another question
srry just got back
cuz if yes, i think it's just the product of how many ways can you pick players for each position
which is 4 x 9 x 8 x 7 x 6 x 11 x 10 x 9 x 8 x 7 x 3
yes i thought so too
but if the order of defender doesn't matter
it could be
4 choose 1 x 9 choose 4 ... and so on
ig so
wait let me send a pic
why is c
a permutation
if we picked
Couple1Person3
it would double count
Person3Couple1
or it wouldn't?
@languid bolt you here?
no problem
a) use combination formula
b) 5 choose 2 (women) * 5 choose 1 (men)
c) 5 choose 1 (choose 1 couple out of 5) * 8 choose 1 (random guy) * 3! (ways a couple and a person can be arranged)
@shy jackal
oh you did that already
anyways, it would double count
wdym
c) solution is 40
but it's permutation so it's double counting
or is it in this case?
since it's correct
wait...
CouplePerson1, Person3, CouplePerson2 should be counted too no?
should be * 3!
is this the correct solution btw
yes
or is it your answer
correct solution
240 is my answer
OHH
i understand
order they're picked arent counted
yes
it shouldnt double count
oh i mean like..
person 1, person 2, person 3
person 2, person 3, person 1
person3 , person 2, person 1
this counts as 1
the order arent counted
it's a N choose K scenario
yeah
it's combination
tbh combination and n choose k both have the same formula, why are the names different nvm they're the same
wait
then we could just do
(10x1x8)/2!
like we can choose 10 people
then there is only one option left
x 8 remain people
/2! duplicates
i c 2
but then
i have one example
so
There is a registration plate
7 symbols
2 alphabet (26 options)
permutations
5 digits (10 options)
yes
but
they can mix together
so it can be
a12345a
or 12345aa
it doesn't matter
multiply by 7!
wait... but what about identical numbers...
12245aa
12245aa
will be counted as 2
kk
this was a correct answer
i did basic combinations
like up
26x26 is permutation
then divided by 2!
to account for duplicates so it doesn't double count
and then same for digits
and then x 7!
oh ok
cuz 7! is ways you can arrange 7 symbols
true
but then in our couple example
shoudn't i also multiply by 3!
since you can also arrange 3 members of committeee in 3 ways
i think no
why
you cant differentiate the people
so how many ways you can arrange the committee doesnt matter
ah i see
lol
but wait
if it was monkeys and humans
then we would multiply
because we could differniate
?
they all have the same position*
you can tell the difference
i understand the concept but i dont know how to explain it
just think of it as distributing 3 "identical" positions to 10 people
wait
anyways....
idk
how to explain
need helper
like i sort of get it but not quite
like i want to know so i don't make a mistake somewhere else
tho i doubt they will help
they usually take a while
or they just dont help
im gonna write it all on paper just to make it easier
wait..
they're not identical
their "position" is different
nvm i still dont know how to explain
like there was then under b)
and it said
0 cannot be in the first place
so
i did
(26 x 26)/2! x (10x10x10x10)/4! all of that x 6!
since there is like 6 positions left
and that was correct
and that 5th 10
became 1
since only 1 option
i dont rlly understand now
lets just wait until someone come
_ _
context: there are 5 couples (10 people) that are forming a committee of 3 people.
c) there has to be a couple inside the committee
why does the order that they're pick doesnt matter
oh i have an idea
.close this help channel and open a new one
wait
10 people will check the help channel then
idk
but maybe the way my prof did it could help you
<@&286206848099549185>
Why is like this?
7! mistake
@languid bolt thank you regardless
np
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Hello! I seek help in my maths pie chart homework. Could someone please help?

$\frac{\text{Frequency}}{\text{Total Frequency}} * 360\text{°}$
MarveI
np
.reopen
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Need help with part B
to find a minimum, we need to use calculus
ie, find the critical points (F'=0, end points and undefined points) and then use the first/second derivative tests
but it doesnt show any use of diffrentiation in the mark scheme
nvm
i get it now
thanks
.close
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if you know the max of cos(x) is at 0, then you could probably skip the diff
yh it was 25
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A whole number will be upon what? Ex. 6 upon 7, 5 upon 9 but what about whole number
upon 1 (or any number that the numerator is divisible by:
are you asking how to write a whole number as a fraction?
2=4/2=2/1
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struggling to understand how these are solved
I know you have to have a same base everywhere
Chuti
are they 3 times 2^x+2 or (3.2)^x+2
cause normally this is how it should look like $3 \cdot 2$ and not like $3.2$
I suppose its $2^x+2$ since there are no ()
$$3 \cdot 2^{x+2} - 2^{x+3} - 4 \cdot 2^{x-1} = 1$$
$$3 \cdot 2^{x+2} - 2^{x+3} - 2^2 \cdot 2^{x-1} = 1$$
$$3 \cdot 2^{x+2} - 2^{x+3} - 2^{x+1} = 1$$
Then factor $2^{x+1}$ and use exponent laws for that
$$2^{x+1}(3 \cdot 2^{1} - 2^{2} - 1) = 1$$
$$2^{x+1}(6 - 4 - 1) = 1$$
$$2^{x}\cdot 2 = 1$$
$$2^{x} = \frac{1}{2}$$
Now you know that $2^{-1} is \frac{1}{2}$ so x = -1
tysm @gray ingot
@patent swallow Has your question been resolved?
Chuti
2^2 x 2^(x-1)
= 2^(x-1 + 2)
= 2^(x+1)
@patent swallow Has your question been resolved?
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a wire that is 44cm is shaped like a rectangle, is it possible to find the area?
Let x be one side of the rectangle, how would you express the other side?
no, unless you mean the maximum possible area across all such rectangles
nvm.
yeah
mb
i mean maximum possible area
it's still yes
you can find the area in terms of the side lengths
it'd be some function that you can find a maximum point for
A quadratic
a quadratic function?
Yeah
it could be a quadratic, idk haven't thought that far
.
assuming length and breath is x and y
x + y = 22
and you need max value of xy
yes that's what im trying to find
and another question, the area of a square is larger than a rectangle right?
no
not necessarily
squares are rectangles
yeah it would be easier if you tried somehow connecting the two eq
well ok you want the area in terms of some variable
so you can differentiate it and set it to 0 to find maximum
you know that x + y = 22
what else do you know about the side lengths?
(remember you are trying to find area here)
length x width = area?
or ... if you dont wanna use calculus you could try forming a quadratic
In this case conpleting the square might give a better unserstanding of the problem
using these 2 equations can you realise that if f(x) or f(y) = A, you can find the derivative?
Hmm I don't think you need all that. Let x be one side of the recentagle, the other side is 44 - 2x = 2y, (44-2x)/2 = y. Hence the area is x(44-2x)/2.
well ok that's true, if you aren't up to calculus you might be better off doing completing the square
yeah, but i need the values
not really
22-x = y btw
you need to find the highest x(22 - x) can go@languid bolt from these 2 eq
can u guys tell me the question in order to help?
there's enough people helping already, thanks for offering to help though
ok
ok ima try
do you understand where x(22 - x) comes from
if you ever wanna find the original ques... you could check pinned messages
because that is very important
yeah
side = x
other side = 22-x
well guys the problem asks wether it is possible to find the area
wait...
so due to lack of information it is not possible
we're trying to find the maximum value
for the area
ohhhh
please read the entire thread for better context
i didnt know
btw, the closer a rectangle is to a square, the higher the area right?
yes
although i would use the word greater
there are infinite other measures
what are you saying
for integers*
lol
youre still missing many others
what do you mean?
highest possible value is 121
x = 1 and y = 21 for ex
area = 21 * 1
,w plot y= x(22-x)
yeah
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you couldve done x + y > 2sqrtxy but seems like you guys like the hard way
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K
Expression:
My answer
The supposed answer (number 15)
My problem is that I do not know how did i get the incorrect answer
√(1/4) = 1/2
How 2 doesn't go into 1
hmm?
$\sqrt{\frac{1}{4}} = \frac{1}{2}$ since $\newline \bigg(\frac{1}{2}\bigg)^{2} = \frac{1}{4}$
kinglacto
We can just add an exponent when we want?
what?
The exponent is negative
So we have to flip the 1/3
That becomes 9, 9-5 is 4
There is no exponent next to the 4
Oh yeah, this is order or operations btw
the square root symbol applies for the entire fraction
ngl i thought you were trolling
yea
My brain was malfunctioning my bad
np
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May I know how to solve this?
This is my working and after I do integration I got 0 for the final answer
Not sure which steps I did wrongly
@torn isle Has your question been resolved?
<@&286206848099549185>
i dont think you did that incorrectly. youre right that F • dr is 7sin²tcost + 3 sint cost
Yea, but there’s a answer for it
which is zero
Hmm… what if the F is in [x,y,z] order?
Given answer us 23/6
idk how that happened
