#help-0
1 messages · Page 759 of 1
is?
8a -5b -5c
yes
right?
yes
yes
ty
Anyone can please help me to solve This? I can't seem to wrap my head around the first move, if I can get the first move, the rest will follow. But I'm stuck
what's the question?
Find the sides
How did I get this sticker?
Anyway, find the sides of the big triangle
i think this can be solved with trig
Yea, just what's the first step. Maybe I'm exhausted and can't see it
I will look at it, give me some time
👍
you can use sin
sin(20) = 425/hyp
sin(20) * hyp = 425
hyp = 425 / sin(20)
,w calc 425 / sin(20)
The second triangle isn't right angled. The angle is only for the small triangle
u can use these formulas even though if the triangles are arbitrary or not
a^2 + 675^2 = 429^2
oh ye i forgot
well
u know this this then
u can also get the hypotenuse of the small triangle with sah coh tao whatever its called
tan(20) = mod/hos
tan(20) = 425/hos
tan(20) * hos = 425
hos = 425 / tan(20)
,w 425 / tan(20)
K
it doesn't really look correct that the side is 951 lol
anyone else need help i'm slightly bored.
can you do justifying steps
😭
but i think it's correct
@alpine sable That tangent ratio only works in right triangles.
The triangle you're using it in isn't a right triangle.
Yh I was wondering as well
@sacred otter The two angles in the bottom middle add up to a straight line, or 180°. So, mark the left one A and the right one 180° - A. Mark the far right angle as B. Mark the top angle next to 20° as 180° - 90° - A = 90° - A . Mark the segment between A and the right angle as x. Mark the right side of the large triangle as y.
Now, the sum of the angles is the right triangle is 180°, so 20° + (180° - A) + B = 180°, so B = 180° - 20° - (180° - A) = A - 20°.
Now, we can use law of sines:
sin(A)/675 = sin(90° - A)/x = cos(A)/x
tan(A) = 675/x
sin(A - 20°)/675 = sin(90° - A + 20°)/(x + 42.5) = cos(A - 20°)/(x + 42.5)
tan(A - 20°) = 675/(x + 42.5)
(tan(A) - tan(20°))/(1 + tan(A)tan(20°)) = 675/(x + 42.5)
Now, we know from earlier that tan(A) = 675/x, so we fill that in:
(675/x - tan(20°))/(1 + 675/x tan(20°)) = 675/(x + 42.5)
Now you have x and a bunch of constants.
That should get you started.
sure let's go into #help-8
Then you can use the Pythagorean theorem once you have x.
That will get you the other two sides.
what did i do wrong @oak chasm
@alpine sable Your tangent = side ratio thing was wrong, since you have a non-right triangle you're doing it in.
20° isn't one of the angles of one of the right triangles.
you mean this calculation?
No, this one before that ^
oh it isn't the angle? what is it then
Yes, the 20° isn't part of a right triangle.
The angle to the left of it is part of the small right triangle.
The angle to the left of it plus the 20° is part of the large right triangle.
But the 20° itself isn't part of a right triangle.
oh well forget it then
question resolved*
is this the same thing as
6/5x
because the numerical coefficient is 6/5 so couldn't the variable go anywhere?
:0
?
what's the question
:/
yes
ty
the answer key says these are equivilant
can someone pls explain how these are equvilant
they're just rearranged
a-b+c = c-b+a
commutative property
this is called the commutative property of addition.
A+B = B+A
this is true in all fields
Mosh
okie ty
yes
that's the reciprocal identity of tan
thanks
lim of cos(1/x) as x->0, why is it undefined?
ABCD is a square.
FD = 2CF
BE = CF
a) Find DG/CF (I found that it is 6)
b) Show that AHFD can be blocked inside a circle (done)
c) Find angle DHF (I need help with this)
then x = 1/u. so you are taking the lim as u goes to inf
Can somebody help me with this?
and cos(inf) is not a well defined expression
the most you can say about it is that it is between -1 and 1
alright this is very simple.
triangle BCF is similar to triangle GAB
yeah
Do you have any exact measurements?
Nope
You can calculate angle AGB though
with inverse tan in triangle AGB or DGF
atan(1/3) which is 18.43494882
i looked at the answer, and it said it DNE
wouldnt there still be an answer, because it still approaches a number, its just that there would be a hole there
no it does not approach a number
cos(1/0) = cos(inf)
there is no such thing as cos(inf)
it literally does not converge to a value
,calc cos(1/(0.1))
Result:
-0.83907152907645
,calc cos(1/(0.01))
Result:
0.86231887228768
,calc cos(1/(0.001))
Result:
0.5623790762907
,calc cos(1/(0.00001))
Result:
-0.99936080743769
can I get some help aswell
what exactly are you having trouble with proving?
Whats the difference between round brackets and square brackets when determining domain and range
square brackets is including the number, parenthesis are not including
so [0, 3) will be from 0 to 3, including 0 but not including 3 (there is a hole at 3)
bump
alright thanks
@tawny condor you said that AHFD is cyclic, correct?
whew this was a tricky one but i found the answer
or what exactly did you mean by "blocked inside a circle?"
,w arctan(2/3)
uh
are those just variables put together?
thats a long one, sure you have to do this exercise and you didn't learn what cosine is?
I don't understand this
Oh
wait
I seeeeee
that's actually very simple
ty
yeah just explaining how
it's tricky if you don't know the cyclic quadrilateral theorems
yeah dw I remember that rule
what is cosine im just learning polynomials and then this was my last question 😭
k imma just try smth and see how it goes lol
@alpine sable you aren't supposed to know that at all then
have u learned trigonometry?
yeah it was just a bunch of letters
that were variables put together
idk
it just says this
the question is whether f(x) = cos(x) + x is a polynomial
which it is not
well it sort of is but not really. infinite polynomials are not polynomials
me = confusion
don't worry about it. a polynomial is just something that looks like this:
hehe
$\sum\limits_{k=0}^n a_kx^k = a_0x^0 + a_1x^1 + a_2x^2 + ... + a_nx^n$
why would u use sigma
pretty sure they didn't see sum
daveie
EndTimes
Dave is in 7th grade
where the sequence $a_k$ are the coefficients of the powers of x
EndTimes
I mean strawberry
sigma notation is very easy. i can teach you how to use it if you want
teach they integrals afterwards 😂
well if you insist. reimann sums are not too difficult to explain
and u can end with topology
and if they want a little challenge
u can teach them Inter-Universal Teichmuller Theory or Prime Dimensional Matrices
wtf
can anyone confirm the last one? pls
that's not injective, clearly there are several x's for the same y
oh wait
miss read n with 1 right away
f(n) = n/2 if n is even
f(n) = -(n+1)/2 if n is odd
np
69420
wdym?
69420
it can
what are u talking about
but ye xd
post the question
and dont ping helpers right away
Ok.. also it's very unclear what's in what
secsecx-tanx for example
Mathematics
@everyone
Lol
how do we do b bit?
n/4
is used to find lower quartile
but the number are starting from 150
so i did 190-150
which is 40
40/4
=10
150+10=160
and 160 is included in 150<h<=160
but the answer key says thats wrong
please tell me where i made a error
Help, I need to know what X is. And I need to understand how you got it because I need to transfer that into JS for a project I'm working on.
3.67X + X = X(3.67+1) = 4.67*X
ok hold on i messed something up here
Oh really?
8720=(X*0.0367)+X
the final number is the sum of the unknown number plus 3.67% of the unknown number
$8720 = X(0.0367 +1) \implies 8720 = X(1.0367)$
It just defines x as 1?
You are getting your numbers mixed up.
Is it 0.037 or is it 3.67%?
Those values are different
its 3.67%. i thought i could write 3.67% as 0.0367. is this incorrect?
you wrote 0.037 instead
Yes that is correct. But 3.67% is NOT 0.037
Pealover
Am i stupid lol, 1 is 100% 0.1 is 10% 0.01 is 1% correct?
oh no
i am stupid ok, ok i see
hold on
yes
3.67%
im sorry
i misunderstood his question
8720=(X*0.0367)+X is the final question i need help with.
0.0367X + X = X(0.0367+1) = 1.0367*X
Wait what did you do here? 0.0367X + X = X(0.0367+1)......how did you getX(0.0367+1)
factorization
This is called the "distributive property"
$ab + ac = a(b + c)$
Pealover
Where did the 1 come from
X/X=1
because $X/X = 1$
Pealover
so we are left with 8720 = 1.0367*X
yes
so divide both sides by 1.0367?
exactly
OH MY GOD
i knew it had to deal with 100%+ but i lost my train of thought and couldnt get it back thank you so much
np
try write sqrt(32) in terms of sqrt(2) so you can combine the two terms. if you need guidance on how to do that say it
if its the rationality part you're struggling with then say that
I just forgot how to simplify 
Yeah that's what i was thinking
How would I work this out, not the answer, just how do I work it? One bag of fertilizer will cover 1,225 ft2 of lawn. A front lawn is approximately 115 ft by 100 ft, and the back yard is approximately 130 ft by 100 ft. How many bags of fertilizer will be needed to fertilize both the front and back yards
you are given a few key pieces of information:
how much area a bag can fill
the side lengths of one of the areas
the side lengths of the other area
yes that I understand but what do I do with it, I have not had to do this yet?
do I add? divide what?
think about it for a second
you know how much each bag can fill
so the first thing we want to find
is how much area we are looking to fill up
how would you go about that?
How many bags of fertilizer will be needed to fertilize both the front and back yards
reading that^
what are we tring to fertilize?
the front and back yard
right, so it follows that we want to find out the areas of the front and back yards
so how do I find the areas?
read the question and find the information given
A front lawn is approximately 115 ft by 100 ft, and the back yard is approximately 130 ft by 100 ft.
it's safe to assume these are rectangular areas
not sure where your going
do you know how to find the area of a rectangle?
no
i'm assuming you're in algebra 1?
yes but Ineed to undertand can you tell me the steps I need to take?
yes
the question asked us "How many bags of fertilizer to fertilize both the front and back yards"
so our solving process is as follows:
- find out the total area we want to fertilize
1a. this is composed of the front and back yards, so we must find the area of both of those
1b. sum up those areas
- create an equation that tells us how much area X bags will give us
- solve that equation when the area we want to fill is equal to that of the front and back yards together
so let's look at point 1.
the front and back yards are rectangular, so to find their areas we need to do length * width
A front lawn is approximately 115 ft by 100 ft
the length is 115ft, and the width is 100ft. @proud estuary what is the area?
its not 11 everywhere
11,500
yes, and get used to adding units at the end
in this case: 11500 ft^2
alright now @proud estuary do you think you can find the area of the back yard?
13,000
yes
@proud estuary what would be the total area then? (look at what i'm replying to)
24,500
great
this is the tricky part
how much area can we fertilize with 1 bag?
1225
exactly, so how much would 2 bags be able to fertilize?
2450
yup, so i think you understand how that works
so we can say that X bags will fill up an area of 1225 * x ft^2
so we create a function A(x) = 1225x
<@&268886789983436800>
which tells us the area fertilized by x bags
the final step is finding the number of bags from that function
@surreal meadow thank you so much I got it, it is 20 bags
awesome 🙂
Got time for one more?
yes i do
A commercial airline plane with 250 passengers on a 3250 km flight from Seattle to Detroit averaged 650 kilometers per hour and used fuel at a rate of 5000 liters per hour? What is the fuel consumption in gallons per passenger (gal/passenger)
thank you @ namington
ok, after you've read the question, can you tell me how much fuel the plane uses per hour?
5000 liters
3250km
ok so you understood the info given. let's move forward
we know that the plane travels at 650 km/h
and the flight is 3250km long
so how many hours will it take for the plane to get to its destination?
5hr?

(given that it uses 5000 liters per hour)
25000?
exactly
so now we want to find the final ratio, gallons/passangers
can you write a ratio of liters/passanger from what we've solved so far?
this part I do not understand
alright, so the question is asking us for the fuel consumption per passenger
and we know the following: 25000 liters of fuel were used up to transfer 250 passengers
so the ratio of fuel (in liters) to passengers is 25000:250 or $\frac{25000}{250}$
maximo
does that make sense/look familiar?
no sorry it does not
let's think of it the other way around then
250 passengers traveled with 25000 liters of fuel
so 250 passengers used up 25000 fuel, how much fuel did each passenger use up?
this is likely wrong but 1 gallon?
let me ask a different question, if 2 people ate 10 apples, how many apples did each person eat? (assuming the apples are distributed equally among the people)
5
right
so now instead i'll ask
2 people used up 10 liters of fuel
how much fuel did each person use?
5
perfect
now let's use bigger numbers
25000 liters of fuel were used for 250 passengers
how many liters were used for each passenger?
100
yeah

so the fuel consumption in liters per passenger is 100 liters/1 passenger
did that make sense?
no
what about it didn't make sense?
not quite
ohhh
we now have a fuel consumption in liters/passenger
but we want gallons/passenger
do you happen to know the conversion rate of liters->gallons?
no
yeah same here, but i'm assuming the question provided it
^ that right there is a good starting point
we know that 1 gallon = 3.78541 liters
so how many gallons are in 100 liters?
26.4172
looks about right
so the answer is 26.4
26.4 gallons/passenger
@surreal meadow I wanted to say thank you, your a life saver, I would not have figured these out without your help, you are very appreciated.
here to help 

Might be easier to figure out what volume the tetrahedron doesn't take up
Realize there's 4 of the exact same "missing volume"
yeah but how do I do that?
Can you find the length of any of the sides of the tetrahedron?
1st Diagonals of the square. 2nd sides of the square. 3rd Angle between diagnal and the sides are 45 degrees (maybe use sin or cos here...) Then you can calculate the volume of the one of the "missing volumes"
pythag>
A tetrahedron fits perfectly inside a unit cube
Kek
do you know what each of those words mean?
I guess the fit isn't really perfect
a unit cube has side lengths of 1
a unit cube is 1x1x1 right?
if you see "unit (shape)" chances are it's defining feature is of length 1
Find the inverse s of -1959 modulo 979 such that 0 ≤ s < 979. You must show all the detailed steps.
it's correct
how to prove this cos^4 x + cos^2 x sin^2 x = cos^2 x
oh jesus my brainnn
How would I write 4x^(10/3) with a root and whole exponent? I'd assume it to be curt(4x^10) but I'm really not sure--sorry.
I have a really icky foundation in math because I moved from Sweden to the United States when I was young. My american schools have had a lot more rigorous math programs than my Swedish school did.
10/3 = (a/3) + (b/3)
where a is the greatest integer less than 10
Curt(4x^10) is correct I believe
assuming curt is supposed to mean cube root, it is not
where n and a are integers
I don't quite understand what the bot is doing but yes, something like this
edited for brevity
but you are familiar enough with the rules of exponents, yes?
@rough zinc
I mean
I obviously have some glaring holes with exponents
so I guess the answer would be not entirely
x^(a+b) = (x^a)(x^b)
10/3 is the sum of _ and _
both are something over 3
one of them is the greatest integer less than 10
the other is made obvious once you know the first addend
am i missing something or is that just nine
oh so 30
eh?
but how does that help?
x^(a+b) = (x^a) (x^b)
probably didn't pay attention to this earlier
I checked with a dummy number and it is this
or?
do you not understand what this is saying?
I do but i don't see how it helps?
4x^3+cbrt(4x)?
oh sorry that's not meant to be there
but that doesn't make sense factor it in and it's 9 not 10
ok yeah right
here there's a three and a three but how does that make a 10 and a three?
because cubrt(4x) = (4x)^(1/3)
Because 10/3 is equal to 3 and 1/3
also sick bot
yeah, you forgot already about how you got 3 (from 9/3)
Yies
Got a quick q
trying to isolate for n on the n^3 summation formula so i can create a program, but just wondering how I could isolate for n to see if I can solve n for some summation of n^3
sorta like this
the line above is where i try to see if I can find a way to isolate for n to solve that n = 2 in that case
where are you stuck
int x^n is x^n+1/n+1 and for cot^2 x is 1+cosec^2 x and int for cosec^2 x is -cot x
what's the Magma for the empty set?
I like to call it George
okay, aside from the startle, since that's my name, i'm out of the loop...
woosh it goes
an empty function
i guess this exists ⊥ → ⊥ → ⊥ but it's kind of weird. are there any uses for it?
no
Oh wow I swear I didn't know your name haha
Can someone help me? There's this question that was asked after the lecture where i can't rlly wrap my head around so insights are welcome
You are given an infinite countable set X and you define X^X is this still countable?
What do they mean by X^X how do you take the power of a set?
My feeling is that it's uncountable take X = N then you have N^N that seems uncountable but it's not rigorous in any way
$X^Y$ is the set of all functions from $Y$ to $X$
Ann
and $X^X$, accordingly, is the set of all functions from $X$ to itself
Ann
aah u need to read it like that okay that makes sense
so it's basically a set made up of bijections
aldus countable since they're all bijections?
no
not bijections
i said all functions
not all bijections
some functions from X to X are not bijections
What doesn't make sense? Do you feel like going to 7th grade is too fast for you?
make a wish kid has the right skills for 7th grade at least
hi
what’s the point of modular inverse if you can solve congruences using extended euclidean algorithm
What does it mean to "solve a congruence"?
Are you talking solving something like:
5x = 2 (mod 23)?
yea
Bad example there's an obvious solution to that one haha
just make it into a diophatine equation and solve for x
You make it sound easy lol
no inverses needed
eh at least there’s a way
for ax ≡ b (mod n)
i see modular inverse is usually introduced after linear congruences in number theory courses
whats the use of it if you cant solve eqns with ir
it
You can solve equations with it kek
I'm wondering what method you're currently thinking of
5x = 2 (mod 167)
I suppose you could just do euclid algo to get:
5m + 167n = 2
But then what if you get asked
5x = 27 (mod 167)?
If you did the exact same amount of work to get the modular inverse of 5, you could do both questions with no extra effort
But if you get 5m + 167n = 2 directly, you now have to repeat the process for 5m + 167n = 27
I guess that's pretty fringe haha, but in general the modular inverse is more info than other alternatives
hey i need some help with my maths project anyone ready for it?
i was going through linear algebra gone wrong:
does anyone know how to do example 1.5? there are no solutions for it 😦
find a 2 by 3 matrix $A$ so that $A+M=M+A=M$ for all $M\in M_{2\times 3}$
Dreadful Encore of Twisted Karma
Hello, in a lesson I was learning beginner trig and in this part of the equation i put 5sin30 and got -4... and my teacher said it was 2.5 not sure how?
oh wait nvm
was using google's calc and it messed it up
i used my normal calc and it works
@alpine sable
You can likely guess it. What matrix in M2×3 would best represent the idea of 0?
a matrix with all 0s?
Exactly haha
... what a useless question 😠
Not at all!
Note what Dreadful has said above, we call this matrix a 0 because it doesn't change any other matricies with addition
This 0 has to exist, or else this isn't a vector space
I guess it is just trivial imo
also what does \mathbb F here mean?
field? what does that mean?
F is an arbitrary field
a vector space of bases?
What form 0 takes is usually trivial, yes.
0's implications are not trivial at all
"a vector space of bases" what
what is a field?
You might have missed fields in your book, take a quick sec to look over it
loosely speaking, a field is a set upon which you can do arithmetic
i know of galois fields with mod arithmetic
i.e. add, subtract, multiply and divide (except by zero)
but what does that have to do with vectors
...so you know the axioms that define a field, yes?
you can divide in fields?
of course you can divide in fields
😮
no... i learned in a weird order 😅
A vector space is two structures squashed together.
The vectors form a group.
The scalars form a field.
mostly to ensure arithmetic works as you would expect it to
"squashed" means the vectors and scalars interact in specific ways
i think i got it? is this right:
a single vector is in a field^n as it is a collection of scalars
but a collection of vectors is a group/vector space?
a single vector is in a field as it is a collection of scalars
no
a vector shouldnt be thought of only as a list of scalars
do fields have an inherent ordering then?
It ends up being the case that all finite dimensional vector spaces can be represented this way haha
But no, that's not why something is a vector
so it provides solutions for all ax ≡ b (mod n) provided a, n unchanged?
@covert agate
Yaya. It solves for all b at once
0hai =]
How often do division-derived branches of the Fibonacci sequence outgrow the main sequence?
for example:
1 1 2 3 5 8 13 21 34
21 / 3 = 7 ; 7 * 5 = 35 ; 35 > 34
1 1 2 3 5 8 13 21 34 55 89 144 233
144 / 8 = 18 ; 18 * 13 = 234; 234 > *233
P.S.: I wish Markdown had colors for highlighting math sequence members for sequence property math... IRC had %C commands...
what’s the point of that
Kek I guess there isn't much point of that
if it’s a single problem
More info with the same amount of work
proving things?
It does provide a bit of insight. That is, every number coprime to n has an "opposite". This helps wrap our heads around what's really going on, algebraically
This modular inverse pairs numbers together nicely
so, does anyone know how often division derived branches of Fibonacci sequence outgrow the sequence itself? (see examples above, where I showed the first two such derivation points)
the first derivation point, 8, produces a very weak branch (8/2=4 ; 4*3=12 ; 12 < 13), 21 is the first derivation point where the branch outgrows the sequence
maybe this is the wrong place to ask this question...
Are you choosing your starting numbers at random?@patent swan
Like in that second example, 144 and 8
no, I choose all Fibonacci numbers divisible by previous fibonacci numbers, 8 is the only way to derive a stronger branch out of 144
Ah I see. Then you multiply by the number after 8, and compare that to the number after 144
divide 144 by 8, multiply result by 13 (next after 8), and compare to 233 (next number)
That's exactly the same as comparing
144/8 to 233/13
Except you only do this comparison when the first is an integer
Actually, that's exactly the same as comparing
144/233 to 8/13
#imagineaplace, dang it hang it!
with non-integers like that, I'd think the outward branches would be more frequent than with an integer-only search
I mean you can choose to only include the search if 144/8 is an integer
But we can make the search more modular with this
the first two integer outward branches (from 21 and 144) had their initial outgrowing by only 1, and were exactly 4 spaces apart within the sequence (members number 8 and 12)
I bet, actually, that this fraction is directly computable
Well, I guess it all is, haha
1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765
bold confirmed, underscore questioned, crossout means weak branch
10824 < 10946
this means 4 isn't quite accurate even for integers
this is important for the statistical mean risk of a double lash within the perimeter (not the twister core itself) of the cyclone, and other statistic mean intensity increases for things that exhibit the golden spiral pattern
it's also important for computing likelihood of double fronts of cyclones and anticyclones giving that extra strength to thunderstorms
living in a place with both sea and mountains nearby, the weather can be quite turbulent at times, and the forecast thing is a mess...
given the initial 1 1 gives a half circle and multiple spirals can emerge from a single completely circular core, I need to know the angular mean for outward branches of fibonacci spirals
what'd be the shortest formula for finding outward branches of the Fibonacci sequence/spiral?
Hey, if y = ax^k how do I write In y as subject?
Take the ln of both sides:
ln(y) = ln(ax^k)
Note the right can be expanded like so:
ln(y) = ln(a) + kln(x)
@clear vessel
its known that AC = CD, how can i show that AC = CD = AD? it looks quite obvious
well circles are symmetrical about the centre
Dude I'm horrendous at math I'm good at English
This stuff blows my mind
Like what does this even mean
?
I'm going in 7the grade and this math stuff blows my mind I suck at math
is there any other info given?
for everything i have studied it hugely depended on how i approached it, stuff that iwanted to learn came easy to me, stuff that i didnt, simply did not
if u can somehow proove CQ=QD
then u can proove using pythagoreas theorem
np
Oh I understand
lol
i was also like you, just approach it differently
enjoy math
Ill take a new approach
im kinda stupid lmao, can also prove it by proving that ACQ is congruent to AQD
5'1 filipino subhuman incel
what is your question
is it just solving the equation?
also both equations are satisfied, not just one of them
,tex He only tested $x = 6$ on
$$\sqrt{3x - 7} + \sqrt{2x - 1} = 0$$
and when it didn't work he said $x = 6$ satisfies $$\sqrt{3x - 7} - \sqrt{2x - 1} = 0$$ and didn't test $$-\sqrt{3x - 7} - \sqrt{2x - 1} = 0$$ or $$-\sqrt{3x - 7} + \sqrt{2x - 1} = 0$$
5'1 filipino subhuman incel
maybe because when he did the first equation, he saw it was 11+11 and so putting a negative sign infront of one term would satisfy the problem?
Your third equation always works if the first works. And the fourth always works if the second works
^ just multiply -1 by both sides to see that
Lmao I am dumb
I got it now, thanks
np
,rotate
use logarithms
uhhh use logarithms? especially take advantage of the property that log_a(a^x)=x
i forgot what logarithms are or i just don't recognize the name in English. what do i do exactly?
ok firstly tho, is that 1.02 or 7.02?
ok
so try to isolate (1.02)^n and then take the log base 1.02 on both sides
this is a giveaway at this point
First write your function as an equation: $k=2500 \cdot 1.02^n$
farbbohrer
then do i take 2500 over to the other side of the =?
multiply so k/2500=1.02^n
yes
now what is this logarithm i have to do to get n
but are there cases where its true without this
how do i enter this into my calculator? (ti 84)
i watch it and understand logs but idk how to enter it
You should have a log button on your calculator. Depending how your calculator works you either can do calculate the log with the correct base or you need to use a trick to calculate it with the correct base.
But you dont need to that for your current task.
You "just" have to rewrite it with logarithms.
Question: What is $log_1.02(1.02^n)$ ?
farbbohrer
farbbohrer
Forget your calculator
It can only calculator the logarithm for the base of 10. But our base is 1.02
then what do i use?
Your brain
lmfao
use ur log rules
u don't need a calc for this
let me ask a similar related question
Question: What is $log_2(2)$ ?
abe
what?
$log_2(16)$ is the question as to what power should I raise 2 to get 16.
farbbohrer
this channel is occupied
So what would $log_{1.02}(1.02^n)$ mean
farbbohrer
which channel can i get my answer from?
to what power do i have to raise 1.02 to get 5000/2500 or 2
any channel that isn't occupied
not quite
do you see that $log_2(2^2)=2log_2(2)$
abe
Maybe you should read or watch a bit more about logarithm
i just want a way to enter log1.02(2) into my calc cause i think i got that far at least.
I will you give a hint how to calculate the logarithm with your calculator (if there are no variables in it).
$log_{1.02}(2)=log(2)/log(1.02)$
farbbohrer
so they're the same?
right side is what you should put in in your calculator
got it but i don't quite understand the inputs yet.
so i have my answer but i don't get how i got there
in the vid u send he entered his formula differently.
$5000=2500\cdot 1.02^n$
farbbohrer
$5000/2500=1.02^n$
farbbohrer
farbbohrer
farbbohrer
Which you have to calculate with your calculator using the trick i posted
$\frac{log(2)}{log(1.02)}=n$
farbbohrer
So we get $n\approx 35$
farbbohrer
Hey there just wondering why we are using sin for i-direction and os for j-direction, can't seem to wrap my head around this
What is the definition of sin and cos?
Yes. You use them in triangles and there they have a definition.
irf
at this point when i need to find the derivative, should i open the parentheses?
Don't need to, use chain rule
whats that
You dont know chain rule, quotient rule and product rule?
i probably do but i dont know how its called in english
ill google it rq
oh yeah i know what it is
ok ill use it thanks
np
i know i dont need to open the parentheses but will it make it easier to solve?
For that, might be like 10 sec faster. But for more complex equations, chain rule saves alot of time
oh ok
help
sry to just keep on asking but how did this happen?
@vivid comet 5000/2500=2. And we use the logarithm on both sides of the equation
thanks a lot. I think i got it for rhe most part.
why can't you come up with a combination of the real and imaginary bits of a complex number such that it's equal to another complex number?
what do you mean?
like why can't we figure out some x +yi = zi
(x != 0)
I understand this is probably wrong? but I wanna know why it's wrong
so you are essentially asking why two complex numbers that have matching real and imaginary parts are in fact equal?
I am asking why we can't find some combination of x and y in this that works?
Can this combination involve multiplication? Or just addition and subtraction?
complex numbers are but points in the complex plane
you are asking whether or not it is possible to have (x,y) describe the same point as (0,z) without x being 0
assuming you intended for x, y and z to be real, of course
I did
that sounds like it has more to do with the construction of the human definition of complex numbers and not a "mathematical truth"
it's a correct answer though I guess
How does subtraction work?
fair point mr far
For all those people who find it more convenient to bother you with their question rather than to Google it for themselves.
I think he's trying to make an argument
Things in math are equal if you subtract them from each other and the solution is 0
gonna go for some meditation be back in 5
@mystic sinew In complex numbers it would be better to argue how can something be equal if there is a distance between those points. And we can easily show that the distance between such points is always greater than x.
What's the answer to this and where can I practice with these types of questions?
3 to 4, i think
codeo
There are 20 more men than women in a movie theater. If 10 more married couples had entered the room, the number of men would have been twice the number of women.
Express the two unknowns in the sentences given above with a system of equations.
Men = M
Women = F
M = F + 20
M + 10 = 2. (F + 10) =>>> Why is not 2.(M + 10) = F+10
codeo
the first equation should be M = F+20
https://www.onlinemathlearning.com/ratio-proportion-gre.html but if you look for quantitative reasoning ratio problems, these are very common and a lot of people struggle with these so theres a lot of practice out there
Thanks guys
are we assuming all 10 entering couples are m/f?
yeah haha
how do u find the area of this?
who pinged me
Break it up unto smaller shapes
what shapes should i break it up to
Uhhh me saying let me google that for you is impossibly based….then deleted messages as this isn’t the place for discussion
Into shapes that you know how to calculate the area of
ok thx
I can see half a circle for example
You dont know how to calculate the area of a circle or triangle or square?
no i know how to do a square but i forgot circle and triangle
I did it like in 7th grade 3 years ago
_Youssef_
do you know how to do 2/1 = -1/3x
Ok first thing, what is 2/1?
2
What do you need to multiply -1/3x to make it be just x?
need help simplifying 32/27 / -1/6
the answer says its -64/9 but i dont know how to get there
Do you know the rule when dividing with fractions?
its something like multiply the reciprocal right
Yes
but i dont know how u would get a 9 on the bottom
nor would that equal -64 on the top
u have to simplify
You have $$\frac{32}{27} * \frac{6}{-1}$$
dldh06
hi guys
You can multiply across, like normal, then simplify or simplify parts of it now
how to manage our time?
Channel busy
oh
I did the multiply by the reciprocal rule
$$\frac {\frac {32}{27}}{\frac {-1}{6}} = \frac{32}{27} \times \frac{6}{-1}$$
so now my answer wouwld be 192 / - 27 / 6
HELLOBELLO
I already told you, this channel is busy
How?
no nvm it would be 192/-27
yeah
Now, simplify
$$\frac{32}{27} * \frac{6}{-1} \equiv \frac{32}{39} * \frac{23}{-1} \equiv \frac{32}{9} * \frac{2}{-1}$$
dldh06
Also, this is a math server. Don't know how this relates to math
Use a linearity test.
For linear functions
f(x + c) = f(x) + f(c)
f(ax) = af(x)
You want to rewrite the equation as
f(y'', y', y) = 0 and apply the tests
Thanks
if i have a set like Q(sqrt(2)) where the elements are of the form a + b*sqrt(2)
(a, b are members of rationals)
if it were a field (which it is) how would i go about finding its multiplicate inverse?
i tried expanding 1 / a + b*sqrt(2)
by amplying with a - b*sqrt(2)
etc
but it's different from a solution i found online
what did you get
ye
denominator should be a^2 - 2b^2 I think
i mean x is a variable
it can be anything
In mathematics, and in other disciplines involving formal languages, including mathematical logic and computer science, a free variable is a notation (symbol) that specifies places in an expression where substitution may take place and is not a parameter of this or any container expression. Some older books use the terms real variable and appare...
dont'know is there a general one
new here
xd!
you can evaluate that expression with anything
in the domain of the expression
@fervent gust now im being asked if "the set of all polynomials with integer coefficients forms a field"
but i've never thought of sets of polynomials before so im confused
basically
help
so i never take algebra before but i have an algebra test is coming, and its extremely imprtant to me
rip
@untold marten Algebra 1?
If so, you can learn it here: https://www.khanacademy.org/math/algebra. It has video lessons and practice problems.
If you get stuck on something, you can ask here.
@fervent gust so is it the set of elements of the form n, nx, nx^2, nx^3, nx^4, ..., (with n any integer)
khan academy also offers easy practice to build up confidence
that also helps me understand things i don't understand
more like $$a_0 + a_1 X + a_2 X^2 + a_3 X^3 ...$$ where $a_0, a_1, a_2...$ are integers
uyitroa
so 1/x is not a polynomial?
nope
yea
theres the trigonometric identity: cos a = sin (90 - a), can i also say that cos 2a = sin (90 - 2a) ?
im just confused
Yes.
alright, thank u
You can replace a with whatever
As long as you do it on both sides, the identity holds
cos(goldfish) = sin(90 - goldfish)
damn now I can't unsee
goldfish better be in degrees :p
Can you write it out as an equation?