#help-10
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i tried to create a matrix from this equation
but it was 4x3
so i thought that determinant would litteraly take a lot of steps
any advice
<@&286206848099549185> anyone
not sure howh would that make it easier
it would make it easier to find the determinant
whatever "the determinant" means
if you have an actual problem statement, post the original question
the equation is .
which one of the affirmations are true:
- if (m = 1, and a = 1) the equation have one unique solution
- if(m = a) the equation have infinite solutions
- if( m != a) the equation doesnt have any solution
the whole problem without the translation
the determinant of a matrix
but not sure if its the way to go
you don't even have a square matrix so why do you think you should use a determinant
oh i forgot, for a moment i thought you can calculate the determinant of every matrix
@tardy epoch any idea how to solve this, been stuck for hour +
since the determinant isnt an option
you are given options for a reason. use them
it's silly to show just the system of equations while ignoring the information in the question
and an absolute waste of helpers' time
sorry for that,
how would i know which one has infinite solutions or not
.
my question was "after using the options , how can i conclure that a system has infinite solutions"
sorry if its a stupid question
anyways thx , i'll try to use the options
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k=(2^p)-1
N=(k^2)-1
prove that (2^p+1) is a factor of N
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why is it >= and not >
if a sequence is always greater than 1/4, but gets arbitratily close to 1/4, then its limit may be 1/4
I understand that however here there is some expression and not exactly a_n
we still have $\lim_{n\to\infty}a_n=\lim_{n\to\infty}a_{n+1}=g$
cloud
so I can treat this expression as a limit on its own?
@tawny tree Has your question been resolved?
this probably just follows from the definition
yes
ooh okay like that I get it now
yes that was in the lecture script
thank you
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hiiii everyone i'm having trouble with understanding gamma functions. how would you solve for (1/2)! any help is very much appreciated 🙏🙏
gamma(1/2), or (1/2)! ?
(1/2)!
1/2 factorial?
Yes
so then we have (1/2)! = gamma(1/2 + 1)
did someone say gamma function
ohhhh i had a small error in my integration i just realized my mistake 😅
tysm guys ❤️
lollll yes
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How do I subtract in different bases such as 6345 in base 7 minues 1362 in base 7 and change numbers between different bases like 42 in base 10 when written in base 5 is
the same way you do in base 10
you just have less numbers
1,2,3,4,5,6,10,11,12,13,14,15,16,20...
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why the mid point between two numbers is (a+b)/2 ?
because thats the average of the numbers
then question becomes why the average is (a+b)/2 ?
if 0 < a < b, then u can define the midpoint as the point in the middle of segment ab between a and b. That is, midpoint = a + [(segment ab)]/2
m = a + (b-a)/2
Which simplifies to (a+b)/2
why did we add half of b-a?
i mean, it makes sense intuitively but that doesn't mean i understand it.
well
Have u used vectors
yes
let a,b,m element of R. a<b and m is the midpoint. thus segment am and segment bm must be equal.
ok ur trolling 😭
am and mb
why did you said that i'm trolling?
too much stuff
By definition
Also, why would you want not to take the middle between the two numbers?
i don't get why adding two numbers then dividing by 2 gives the half between them and i am trying to understand it
Let's say you have a < b
the distance from a to m should be (b-a)/2, right
Yeah, (b-a)/2 is the distance between the midpoint and each of the endpoints
nice
now i get it
a plus this
i was trying to understand linear interpolation but first i have to understand this
okay this makes sense
thank you all. i'm done, how do i close this channel
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If this point is the mid point between am then yes
yes it is
does it becomes a + (b-a)t if we want to generalize it?
when t is 1 it gives b, when t goes to infinity it gives a right?
u can generalize it for any a,b no matter the order with vectors
the components are just A=<a,0>, B=<b,0>
the midpoint would be in M = A + AB/2
.
and if i want anywhere something in between it is A+AB*t where t is a percentage?
yes
for example if t is 100
P = A + AB (100%) = A + AB(100/100)
P = A + AB
P = A + (B-A) = B
so the point is basically just B
and this is called interpolation right?
i have no idea
okay thanks
if u need it with numbers and not vectors you expand AB = B -A
P = A + ABt = a + (b-a)t
i wasn't trolling by the way, sorry for the wrong impression. i didn't mean it
hold on
i have seen this formula 4 years ago
this one
a(1-t) + bt
it didn't make sense intuitively
midpoint is this when t =50% and in one dimension
but yes it comes from P = A + ABt
it just means, start at A, then move along the segment AB from 0% to 100% (0 to 1)
a bunch of annoying terms that are hard to read
construction of desired point is different
if you rewrite it as a + (b-a)t is easier to notice that its just P = A + ABt
in vectors AB = B-A
so AB = <b>-<a>
A vector that points from r0 to r1
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(1-t)r0 is the equivalent of (1-t)a
just in the ugly way
P = (1-t)a + tb = A + ABt = a + (b-a)t
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nothing
just 'simplification' that is not even a simplification. it just makes it harder to read
the nice formula is P = A + ABt
or P = r0 + r0r1 t (the same, whe just changed the name of the vectors)
no, it doesnt mean anything
i know it is nice
but surely it must mean something
if u want to interpret it t would be the % of how much we take of a and what we dont take of b)
(1-t)a + (t)b
if t=0=0%
100% of a + 0% of b
if t = 1 = 100%
0% of a + 100% of b
if t = 0.5 = 50%
50% of a + 50% of b (the formula would simplify to 0.5a + 0.5b)
isn't it (1-t)a + bt
but it is here
ye forget it
okay now im reading it again
t means the % you move in the segment
damn
and how close you are to the endpoints
jokes on you i dont even know what is interpolation
i mean how did you come up with this
i didnt even type what i mean
but still similar idea
(1-t)a + tb read in percentage way
(100%-30%)a + (30%)b as an example (because 1 = 100/100 = 100 (1/100) = 100%
70%a + 30%b
if you think about this, 50%a + 50%b being average would intuitively lead that 70%a + 30%b means that a is weighted more than b
so the number should be to the left side of the midpoint
30% of the entire segment starting from a to b to be more precise
linear interpolation is a method of curve fitting using linear polynomials to construct new data points within the range of a discrete set of known data points i.e. what we did right now
t is f(t)=t but doesn't have to be
not gonna lie, i understand it vaguely, not precisely.
anyways, i gotta go. thanks for everything.
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given: AB=AC=AD
∠BCD=140
∠BAD=???
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why isnt this correct? both of my m and n values are perfect sqaures here and 36 is not a perfect sqaure
@violet ingot Has your question been resolved?
6*6 = 36
Moreover, even if that was not the case, it would not be a counter example to the statement above.
A counter-example has to be m,n such that mn is a perfect square but m or n are not.
so to prove it false, all i have to do is use 1 non-primes that make a prime like 1 and 4 and pick the 3rd option?
I'm not sure what you mean by 2 non-primes that make a prime.
1*4 is 4, which is a perfect square, but both 1 and 4 are perfect squares, so it's not a counter example.
1,3 my bad got confused with a seperate problem
But then 1*3 is not a perfect square
ah
The exercise is to factor some perfect square into non perfect square factors
oh
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Hi just curious is it possible to simplify that further with the factorials
where
Bottom right
Yea
u got 1=1
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how did the radical turn negative here?
i know it has something to do with x approaching negative infinity but how does that work?
As $\sqrt{x^2} = \abs{x}$, if $x$ is negative, you have $\sqrt{x^2} = -x$
@unreal musk
Erm are u sure
Isn’t this just a+b = -(a-b)
In the denominator
(that isn't true either, but it isn't)
(also hiii
)
Hi
I’m pre sure all they did was factor out the negative sign in the denominator but ok
so i would multiply each root by -1 whenever x approaches negative infinity
intuitively
your expression in the first line will be negative
when u multiply by 1/x / 1/x
the x goes into the square root but u lose the information for the fraction being negative
thats not it
There isn't initially a negative sign to begin with, if you divide numerator and denominator by x, you get 6 as the numerator, but to be able to "absorb" the x into the root, you'd write it as -sqrt{x^2}
Oh I’m stupid whoops
Which is where the negative signs come from 
when i multiply by 1/x my expression is negative?
multipy by 1/x / 1/x
as in
(1/x)/(1/x)
ok just before u even evaluate anything and stare at the first line
you know the denominator is going to be positive at least
so your overall expression after limit has to be negative
when you divide top and bottom both by x
and absorb the x into the square root
u are losing 'information'
i see
thanks
just tell me this please, mechanically, if i just multiply by -1 next time x approaches negative infinity will it work out
Basically the argument you're using here is this:
You know that 1/x is negative
Therefore, when you multiply (1/x) *rad(expression)
To account for the fact that this number should be negative,
We write it as -rad(expression/x^2)
Because otherwise rad(expression) is positive
that makes sense
thanks
is that the case only for radical expressions though
Well even roots specifically
because on the top when i multiplied 6x by 1/x it wasn't negative
Probably not the ONLY time but this is specifically an issue for even roots
Because even roots are always positive for real numbers
So when you're expecting a negative number
If you follow the "normal" algebra
You'll lose that information as the phrase goes
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How to solve this problem?
look at rows 3 and 5
I guess the answer is A but i am not sure
Nvm
The last column is the solution column
Since they called it an augmented one
your 3rd row is saying 3y = 4 and your 5th row is saying -3y = 2
assuming we call the variable associated with the second column y
Do you know how to read the row and write the equation for it?
yea
R3 and R5 would be all 0
The first column tells me about the first variable
For example
The first row says
5x + 5y + 5z = 4
Or
5x1 + 5x2 + 5x3 = 4
Two common ways to name 3 variables
The second equation says
4x + 4y + 3z = 4
From the second row
What equation does the third row represent?
3y=4
Solve for y
4/3
Then check what the 5th equation says
-3*4/3=2
No no
It doesnt tell you solutions
It tells you coefficients on the variable
Write it as y
Well
This is fine too
You see that this is a contradiction
That's because the 5th equation implies
y = -2/3
Those 2 equations are giving two different values for the same y
so it's no solu
thank you
Yw
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given the diameter of a circle and the length of a chord, how would I find the distance from the center of the circle to the chord?
have u tried drawing a diagram to start?
if so, try constructing triangles with the chord and the centre of the circle
Yeah, ty
nw
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find the value of $\frac{3}{1!+2!+3!}+\frac{4}{2!+3!+4!}+\dots+\frac{22}{20!+21!+22!}$
Skill_Issue
im fucked 😭
Where is this from
ans choices are
1/2!-1/22!
1/3!-1/22!
1/2!-1/21!
1/3!-1/21!
1/4!-1/22!
seamo 2024 (it just finished like half an hour ago i just wanna cross check)
$T_n = \frac{n+2}{n! + (n+1)! + (n+2)!}$
Astar777
now take n! common
$T_n = \frac{n+2}{n! (1+(n+1)+ (n+1)(n+2))}$
Skill_Issue
$$T_n = \frac{n+2}{n! (n^2+4n+4)}$$
$$T_n = \frac{1}{n! (n+2)}$$
Skill_Issue
$$T_n = \frac{(n+2)-1}{(n+2)!}$$
Skill_Issue
telescope its 1/2!-1/22! right
yes
yes
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There is a scammy way to do this, if you choose n=1
Clearly, this problem has an induction version
and option 1 is the only pair that gives the answer
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What is the formula for this
theres no formula
Ohh
this? this is for finding roots
but you already have roots
so you can do wht death.cv said
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hello
how do i solve this?
i know i can use the two points in a lagrange formula perhaps?
does P(n) = n+3 having 2 solutions suggest its a quadratic?
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@signal glen Has your question been resolved?
what does p(n) = n+3 mean here
First find the polynomial using the given solutions
Then you get another polynomial P(n) = n + 3
Well
It might not be a quadratic
They specified two distinct integer solutions
Then it's solvable fairly easily
how do you know that the function is quadratic though
576a
asuume for now
if it wont work
try smthn else
subtract 1 from 2 to get
just because the function has two integer solutions doesn't mean it can't have other non-integer solutions
If you assume it's quadratic you'll get a answer
yes but that's terrible mathematics because it presupposes something that you don't necessarily know is true
yes but rn there is no other option
u wanna be stuck up here thinking about it
like it has a billion other roots we dont know
the phrasing of the question implies that there is only one possible value of the product
no math is about proof
we shall first try this
Wait
what if this was time bound
The condition for integer roots is that all the coefficients must be a multiple of each other
don't see why that changes anything in principle
ok , we can try something else
i see asuming has faulterd
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hi Layla, before you come in and say "hi Kepe" 
but yes, I need this proof checked over, if anybody is willing to 🙏
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Hello, I have a reflection regarding Dirac's distribution. Given that a distribution is related to a scalar product and that integration is a linear operation, can we deduce that Dirac's distribution is an element of the dual space of the test function space? Additionally, based on the definition commonly used by physicists and engineers, we can observe that the distribution yields a scalar.
,tex $\int_{-\infty}^{\infty} \delta(x) , f(x) , dx = f(0)$
hisitis__
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@low prairie Has your question been resolved?
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@low prairie Has your question been resolved?
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prob rightside
This same argument can be made about the right side
dam its right (i mean ur message its true)
okay maybe its the rightside because each curve is intersected with each other JUST once (yes the way it was given its kinda ambiguous somehow)
Yea it's a very ambiguous loosy goosey 🦆 question
They should have mentioned like y>= 0 instead of "bounded by y=0"
"y>= 0, y<= lnx, y<=4-x^2 " something like that
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Is this correct?
What's wrong with the first graph?
@austere bane Has your question been resolved?
Is this not F(X) = - root(X)
I was going by the logic if I replace X by -ve X then it would be incorrect
-root(X) takes on negative values but the first graph stays above the x axis
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Help
Can this be solved thinking them as addition of angles
Without using the addition of inverse cotangent addition property
Maybe we can establish a pattern for 4k^2 + 3
Then analyse it
<@&286206848099549185>
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Help
How do I mathematically calculate a number to make it tenths, so like 24,385638 -> 24,3
Help pls
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how do u do thois
Just try values for x
$h^{-1}(2)$ is whichever value of $x$ satisfying $h(x) = 2$
cloud
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im super lost on this question
is my work right so far and if yea how do i continue
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4a tips?
@open spoke Has your question been resolved?
3 x 2 * 2 x 1?
Not sure what a's dimensions are exactly
My bad for afk
a is (a1, a2)
(a1, a2)^T right?
as a column vector?
Otherwise it wouldn't make sense
So what does that mean for us?
Sure
.
That is the formula for A * a
It's not
oh i think
I recommend reviewing matrix multiplication
Then it becomes
a11a1 + a12a2
a21a1 + a22a2
a31a1 + a32a2
Yea
Ohh i think i see what we must do, do we basically try to get all of that to be the same as what f(a) is defined as?
3
Meaning of life
Yes, are you familiar with the problem ?
Nevermind, I think I know how to do it. Thank you though
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A water tank develops a leak. Each week, the tank loses 7 gallons of water due to the
leak. Initially, the tank is full and contains 4500. Using GRESA method.
a. How many gallons left 4 weeks later?
b. How many weeks until the tank is half-full?
c. How many weeks until the tank is empty?
GRESA - Given, Required, Equation, Solution, Answer?
anyways, you should approach this problem by setting up an equation that describes how much water the tank has after t weeks
They wanted the given like this type.
example: 𝑎4 = 20, 𝑎9 = −15, 𝑎2024 =?
hmm
well, we should start with this anyhow
ok
at 0 weeks, we have 4500 gallons. after 1 week, we’re at 4493 gallons. after 2 weeks, we’re down to 4486 gallons, and so on
a) Given: - 7 gallons of water, + tank is full and contains 4500, = 4 weeks later
can you write down an equation that describes how much water we’re at after t weeks?
uhh...
let’s call the amount of water the tank has at a given time W
and this number is going to depend on the amount of time, t, that’s passed in weeks
this is your hint 
I’ll start you off
2ml of leakage per minute lmao
when W = 4500, t = 0
when W = 4493, t = 1
when W = 4486, t = 2
and so on
the water is being lost at a rate of 7 gallons a week, so as t increases, W should decrease
what’s the equation we need to write to describe this?
How did you do that-
do what? 
this
well, we know that after each week, the tank has lost 7 gallons of water
yeah?
OHHHH
in general, the equation is going to look like
(Water after t weeks) = 4500 - ??
what goes in the ??
So I have to do this until I reached 4 weeks?
yeah, but you should use an equation rather than subtracting 7 each time
imagine subtracting 7 until the tank is half full 
that would take us like
an hour!
see here
we need to write down an equation to describe the amount of water in the tank after t weeks, to make our lives easier
4 = 4500 - 7?
oh
on the left hand side of the equation, we have the amount of water in the tank at time t
W(t), if you've seen this notation before
W(1) = water in the tank after 1 week
W(2) = water in the tank after 2 weeks
...
W(t) = water in the tank after t weeks
as a result, the right hand side of the equation should depend on t
because the water in the tank is intrinsically tied to the amount of time elapsed
So I have to use this method?
well, that was to give you ideas
subtracting 7 all the way down is really slow and annoying
oh
we'd like to do better
W(t) = 4500 - ???
the ??? should depend on t, because the left hand side depends on t
I promise, once we have this, our lives will be so much easier
maybe I'll write this out again, more suggestively
So... time is missing!
Ohhh
so we know that W(0) = 4500, right?
then 7 is the water?
7 gallons per week
Yeah
okay
so now W(0) = 4500 - what?
I promise this is relevant
7(1) = 4500

that seems a little off
W(0) = 4500
after 0 weeks, we have 4500 gallons in the tank, yeah?
nothing has leaked out yet
Yes?
awesome
now let's plug 4500 into our equation, even though we don't know what it is yet
4500 = 4500 - ???
what should ??? be, in this case?
4500 = 4500 - 0

now, after one week, we know that the tank loses 7 gallons, right?
so it's at 4493 gallons remaining
Yes
down from 4500 a week ago
nice
now let's plug it in
4493 - 4500 - ???
what's ??? now?
How did you get that answer?
4500 gallons - 7 gallons = 4493 gallons
Oh okay
right, so this
OHHH CONVERT 1 WEEK TO TIME
we don't even need to think about weeks or gallons, technically
we just need to solve this equation for ???
and keep doing this until the pattern is obvious
that's how we'll find what ??? is in general
Okay so we have 1 week now. therefor, Convert 1 week to hours to get the time since it's just dates
agh
I don't think that's what you want to do 
weeks are a unit of time here
nothing to convert
oh
t = 1 means 1 week has passed
4493 - 4500 - 7?
Shouldn't this be 4493 = 4500 - 7?
14?
and we saw earlier that ??? = 0, when t = 0
time
it clearly depends on what t is
the week?
I want you to write something like ??? = at, where t is the number of weeks elapsed, and a is a number you should find
that is, W(t) = 4500 - at
what is a?
....
a is a number, but what number should it be? 
7?
‼️
well done! 
now we have an expression that tells us the amount of water in the tank after t weeks
W(t) = 4500 - 7t
okay
so after 4 weeks, what do we have?
4 weeks means we want to find W(4)
and we can do that by plugging in t = 4
W(4) = 4500 - 7(4)
W(4) = 4500 - 7(4)
W(4) = 4500 - 28
W(4) = 4472
That's the answer?
indeed!
the tank has 4472 gallons of water left, after 4 weeks
congratulations!
you did part a)!
A water tank develops a leak. Each week, the tank loses 7 gallons of water due to the
leak. Initially, the tank is full and contains 4500. Using GRESA method.
a. How many gallons left 4 weeks later?
Given: - 7 gallons of water, + tank is full and contains 4500, = 4 weeks later
Requirement: W(4) is the number of gallons left 4 weeks later
Equation: W(t) = 4500 - 7t
Solution: W(4) = 4500 - 7(4)
W(4) = 4500 - 28
W(4) = 4472
Answer: There are 4472 gallons left 4 weeks later.
b. How many weeks until the tank is half-full?
c. How many weeks until the tank is empty?
W(4) is required
the equation is probably, if I had to guess, W(4) = 4500 - 7t?
I'm not too familiar with this method of writing an answer, my apologies
correct?
It's fine
sure thing, but I would probably mentioned under "Required" that W(4) is the number of gallons left, 4 weeks later
so
Okay
ah, hold on
Hm?
Equation: W(4) = 4500 - 7t
it should be W(t) = 4500 - 7t
not W(4)
W(4) is 4500 - 7(4)
Ah okay

correct?
Okie lemme write it and we can do part b
no problem
A water tank develops a leak. Each week, the tank loses 7 gallons of water due to the
leak. Initially, the tank is full and contains 4500. Using GRESA method.
a. How many gallons left 4 weeks later?
Given: - 7 gallons of water, + tank is full and contains 4500, = 4 weeks later
Requirement: W(4) is the number of gallons left 4 weeks later
Equation: W(t) = 4500 - 7t
Solution: W(4) = 4500 - 7(4)
W(4) = 4500 - 28
W(4) = 4472
Answer: There are 4472 gallons left 4 weeks later.
b. How many weeks until the tank is half-full?
c. How many weeks until the tank is empty?
We can procceed

part b wants you to find the amount of time it takes until the tank is half full
that is, we wanna know when W(t) = 0.5 * W(0)
0.5 * W(0) because the tank is full at 0 weeks, and 0.5 cuts that number in half
Ah okay
that is, W(t) = 0.5 * 4500 = 2250
so "when W(t) = 2250, what is t equal to?" is the question we'd like to answer for part b
does that make sense?
Yes
Yes
we now also have W(t) = 2250
since 2250 and 4500 - 7t are both equal to W(t), we can equate them
like this -> 2250 = 4500 - 7t
Where did you get 2250
tank is half full means W(t), the water in the tank at time t, is equal to 0.5 * W(0), since W(0) is the tank at full capacity
but we know that W(0) = 4500, so W(t) = 0.5 * 4500 = 2250 
I see
now it's just a matter of solving this equation for t 
do you see how our work earlier is paying off?
W(t) = 0.5 * 4500 = 2250
2250 = 4500 - 7t
we don't need to subtract 7 a bunch of times
BWAHAHAHA Yeah
we just solve for t and get our answer
so, 2250 = 4500 - 7t
can you solve this for t? 
W(t) = 0.5 * 4500 = 2250
2250 = 4500 - 7t
2250 - 4500 = - 7t
-2250 = -7t
divide both sides
321.428571429 = t
looks good!
but, I suspect we don't really want a decimal week 
does the problem only want whole numbers?
W(t) = 0.5 * 4500 = 2250
2250 = 4500 - 7t
2250 - 4500 = - 7t
-2250 = -7t
divide both sides
321 = t
ah, you actually want 322, I think
because after 321 weeks, the tank still has a little more than half its water left
whereas after 322, it's less than half
you could also just leave it as t = 321.428571429, but idk how well your teacher will take this answer
maybe they take it very well, maybe not
idk
If we tried to round up till will look like this
321.43143
mhm
So it's still 321
well yeah, about 321 or 322 is the correct answer
it's just a little ambiguous rn, cause idk if your class accepts decimals answers
if they do, we can just move on
if not, we'll need to change the answer to either 321 or 322
So that's the answer?
A water tank develops a leak. Each week, the tank loses 7 gallons of water due to the
leak. Initially, the tank is full and contains 4500. Using GRESA method.
a. How many gallons left 4 weeks later?
Given: - 7 gallons of water, + tank is full and contains 4500, = 4 weeks later
Requirement: W(4) is the number of gallons left 4 weeks later
Equation: W(t) = 4500 - 7t
Solution: W(4) = 4500 - 7(4)
W(4) = 4500 - 28
W(4) = 4472
Answer: There are 4472 gallons left 4 weeks later.
b. How many weeks until the tank is half-full?
Given: - 7 gallons of water, + tank is full and contains 4500, the tank is half-full = 0.5
Requirement: t when W(t) = 2250
Equation: W(t) = 0.5 * 4500 = 2250
Solution: W(t) = 0.5 * 4500 = 2250
2250 = 4500 - 7t
2250 - 4500 = - 7t
-2250 = -7t
divide both sides
321.43143 = t
Answer: There will be 321.43143 weeks until the tank is half-full.
c. How many weeks until the tank is empty?
Correct?
honestly, it might be good enough, but I'd use 322 instead of 321 as the answer, if I had to round 
also, the requirement is probably smth like "t when W(t) = 2250"
Is everything correct?
W(t) = 2250, not 225
and I still feel like 322 is the better answer, but if you insist, we can accept 321
referring to this, btw
Requirement: t when W(t) = 225
But the logical fact is the decimals doesn't round up to 322
you're correct about rounding, but that's technically not what we care about here
we care about when the tank is actually at half capacity
and when t = 321, the tank is still a little bit over half capacity
at t = 322, it's a little bit under
so t = 322 is the first whole number for which the tank is actually less than half full
They are both the same when it comes to decimals
I'm pretty sure we do not really care about decimals in this problem
we care about when the tank is at less than half capacity
at the same time both have problems
1 is under
1 is over
They both have problems towards the amount of the tank if we wanted whole numbrs
of course, but 322 satisfies the contraint of being the first number for which the tank is actually at half capacity
321 does not
of course, none of this matters if we could just use t = 321.428571429 
Bruh ykw I'm rounding up and still keeping the decimal
I mean, it is your choice in the end haha
I don't really know what the teacher wants
I would just use t = 321.428571429, honestly 
Were literally debating satisfaction and logical analysis of the half capacity
A water tank develops a leak. Each week, the tank loses 7 gallons of water due to the
leak. Initially, the tank is full and contains 4500. Using GRESA method.
a. How many gallons left 4 weeks later?
Given: - 7 gallons of water, + tank is full and contains 4500, = 4 weeks later
Requirement: W(4) is the number of gallons left 4 weeks later
Equation: W(t) = 4500 - 7t
Solution: W(4) = 4500 - 7(4)
W(4) = 4500 - 28
W(4) = 4472
Answer: There are 4472 gallons left 4 weeks later.
b. How many weeks until the tank is half-full?
Given: - 7 gallons of water, + tank is full and contains 4500, the tank is half-full = 0.5
Requirement: t when W(t) = 2250
Equation: W(t) = 0.5 * 4500 = 2250
Solution: W(t) = 0.5 * 4500 = 2250
2250 = 4500 - 7t
2250 - 4500 = - 7t
-2250 = -7t
divide both sides
321.43143 = t
Answer: There will be 321.43143 weeks until the tank is half-full.
c. How many weeks until the tank is empty?
empty...
So is everything correct?
same thing as in part b!
WAITTT
waiting!
Is everything correct?
seems good to me
Okie lemme write it down rq

A water tank develops a leak. Each week, the tank loses 7 gallons of water due to the
leak. Initially, the tank is full and contains 4500. Using GRESA method.
a. How many gallons left 4 weeks later?
Given: - 7 gallons of water, + tank is full and contains 4500, = 4 weeks later
Requirement: W(4) is the number of gallons left 4 weeks later
Equation: W(t) = 4500 - 7t
Solution: W(4) = 4500 - 7(4)
W(4) = 4500 - 28
W(4) = 4472
Answer: There are 4472 gallons left 4 weeks later.
b. How many weeks until the tank is half-full?
Given: - 7 gallons of water, tank is full and contains 4500, the tank is half-full = 0.5
Requirement: t when W(t) = 2250
Equation: W(t) = 0.5 * 4500 = 2250
Solution: W(t) = 0.5 * 4500 = 2250
2250 = 4500 - 7t
2250 - 4500 = - 7t
-2250 = -7t
divide both sides
321.43143 = t
Answer: There will be 321.43143 weeks until the tank is half-full.
c. How many weeks until the tank is empty?
We can procceed
alright
empty means W(t) = 0
now it's just the same thing as part b; we gotta solve for t!
W(t) = 0 * 4500 = 0
0 = 4500 - 7t
0 = 4500 = - 7t
-4500 = -7t
divide both sides
642.857142857 = t
correct?
it's all correct except that I'm not sure what the very first line is supposed to mean
oh sorry
correct?
,calc 4500/7
Result:
642.85714285714
A water tank develops a leak. Each week, the tank loses 7 gallons of water due to the
leak. Initially, the tank is full and contains 4500. Using GRESA method.
a. How many gallons left 4 weeks later?
Given: - 7 gallons of water, + tank is full and contains 4500, = 4 weeks later
Requirement: W(4) is the number of gallons left 4 weeks later
Equation: W(t) = 4500 - 7t
Solution: W(4) = 4500 - 7(4)
W(4) = 4500 - 28
W(4) = 4472
Answer: There are 4472 gallons left 4 weeks later.
b. How many weeks until the tank is half-full?
Given: - 7 gallons of water, tank is full and contains 4500, the tank is half-full = 0.5
Requirement: t when W(t) = 2250
Equation: W(t) = 0.5 * 4500 = 2250
Solution: W(t) = 0.5 * 4500 = 2250
2250 = 4500 - 7t
2250 - 4500 = - 7t
-2250 = -7t
divide both sides
321.43143 = t
Answer: There will be 321.43143 weeks until the tank is half-full.
c. How many weeks until the tank is empty?
Given: - 7 gallons of water, tank is full and contains 4500, the tank is empty = 0
Requirement: t when W(t) = 2250
Equation: W(t) = 0 * 4500 = 2250
Solution: W(t) = 0 * 4500 = 0
0 = 4500 - 7t
0 = 4500 = - 7t
-4500 = -7t
divide both sides
642.857142857 = t
643.143 = t
Answer: There will be 643.143 weeks until the tank is empty.
Correct?
642.857142857 = t
643.143 = t
eh?
I round it up
if you're gonna round, you should drop it 
JUST ITS ACCURATE
oh okay
A water tank develops a leak. Each week, the tank loses 7 gallons of water due to the
leak. Initially, the tank is full and contains 4500. Using GRESA method.
a. How many gallons left 4 weeks later?
Given: - 7 gallons of water, + tank is full and contains 4500, = 4 weeks later
Requirement: W(4) is the number of gallons left 4 weeks later
Equation: W(t) = 4500 - 7t
Solution: W(4) = 4500 - 7(4)
W(4) = 4500 - 28
W(4) = 4472
Answer: There are 4472 gallons left 4 weeks later.
b. How many weeks until the tank is half-full?
Given: - 7 gallons of water, tank is full and contains 4500, the tank is half-full = 0.5
Requirement: t when W(t) = 2250
Equation: W(t) = 0.5 * 4500 = 2250
Solution: W(t) = 0.5 * 4500 = 2250
2250 = 4500 - 7t
2250 - 4500 = - 7t
-2250 = -7t
divide both sides
321.43143 = t
Answer: There will be 321.43143 weeks until the tank is half-full.
c. How many weeks until the tank is empty?
Given: - 7 gallons of water, tank is full and contains 4500, the tank is empty = 0
Requirement: t when W(t) = 2250
Equation: W(t) = 0 * 4500 = 2250
Solution: W(t) = 0 * 4500 = 0
0 = 4500 - 7t
0 = 4500 = - 7t
-4500 = -7t
divide both sides
643 = t
Answer: There will be 643 weeks until the tank is empty.
Correct?
I would probably keep it as a decimal, tbh 
if your answer for part b was a decimal, your answer for part c should be too
JUST IT'S FINE
😭
it's just about consistency, sorry 
if both answers were decimals, it's okay
if both are whole numbers, it's okay
but one of each feels... iffy
t = 643.143 there this is rounded up
A water tank develops a leak. Each week, the tank loses 7 gallons of water due to the
leak. Initially, the tank is full and contains 4500. Using GRESA method.
a. How many gallons left 4 weeks later?
Given: - 7 gallons of water, + tank is full and contains 4500, = 4 weeks later
Requirement: W(4) is the number of gallons left 4 weeks later
Equation: W(t) = 4500 - 7t
Solution: W(4) = 4500 - 7(4)
W(4) = 4500 - 28
W(4) = 4472
Answer: There are 4472 gallons left 4 weeks later.
b. How many weeks until the tank is half-full?
Given: - 7 gallons of water, tank is full and contains 4500, the tank is half-full = 0.5
Requirement: t when W(t) = 2250
Equation: W(t) = 0.5 * 4500 = 2250
Solution: W(t) = 0.5 * 4500 = 2250
2250 = 4500 - 7t
2250 - 4500 = - 7t
-2250 = -7t
divide both sides
321.43143 = t
Answer: There will be 321.43143 weeks until the tank is half-full.
c. How many weeks until the tank is empty?
Given: - 7 gallons of water, tank is full and contains 4500, the tank is empty = 0
Requirement: t when W(t) = 2250
Equation: W(t) = 0 * 4500 = 0
Solution: W(t) = 0 * 4500 = 0
0 = 4500 - 7t
0 = 4500 = - 7t
-4500 = -7t
divide both sides
642.857142857 = t
Answer: There will be 642.857142857 weeks until the tank is empty.
why are you rounding up? 
BECAUSE MRSJGGEOIJOUOGBGOI
Correct?
Okie

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how would one use the sine ratio to solve this?
the marking schemes suggests using a "sine ratio"
not the cosine rule
i do not comprehend how this would work
thanks :)
@analog rivet Has your question been resolved?
<@&286206848099549185>
@analog rivet Has your question been resolved?
do you know how to solve something like this?
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Is there a general algorithm that isnt numerical for finding x in a sum from i=0 to x of f(i) that equals K, when K and f(x) are known?


