#help-0
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what is the derivative of e^(1-x)
i thought it was itself because i thought d/dx(e^x) = e^x
solutions say its negative i dont undertsand how
why do i have to use the chain rule here
sorry i think im mostly confused on when the chain rule is used
$[e^{f(x)}]’ = e^{f(x)} \cdot f’(x)$
Stephen
It’s always used, you just don’t see it sometimes
For example
$[e^x]’ = e^x \cdot [x]’ = e^x \cdot 1 = e^x$
oh
Stephen
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<@&286206848099549185> hi, i dont understand anyth from this question
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@vast stump Has your question been resolved?
See this solution for first part
ahh
Is it clear
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x = 122 ?
a car travels a disctance of 52000 m is 15 minute whereas a train covers 65km in 45 minutes find the ratio of thier speeds
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Did you try finding both in km/minute and comparing them?
@signal shale Has your question been resolved?
It's not their channel btw
anyone ?
No guarantee i can help, but can you give a clearer picture of whats been written?
I see 3 & 4 at the bottom but can't read the rest
u know inscribed angle theorem?
there's only one
well there's only one theorem
so basically u know the circle arc measures add up to 360
I have no idea what are you talking about
idk if its correct but i got 128
yeah it doesn't matter
howd you get it
an angle is an angle
soo what does this has to do with the question
yeah but dividing it like that gives you a quadrilateral in a circle
yeah I got 128
I used different wY
way
so basically
the red arc is double the 127°
so it's 254°
and the blue arc is double the 105°
so it's 210°
but the circle can only add up to 360°
so the overlap
is
464-360
= 104
so
how do you know the red arc is double the 127
I'll show u
its a skill you naturally develop when doing geometry problems
drawing these lines sometimes help simplify the problem into something doable
so there's more than 1 way to solve this huh
yeah
can you show me how you also do it if you dont mind with your line dividing method shioshi
yeah
that's the central angle
127 x 2 right
yea
the center
then what do I do after that
anyways so you have a 6 sided shape here inside the circle right, you draw a line through the middle two points
now you have two shapes with only 4 sides, and since those 4 sides all touch the circle, you know that opposite angles add to 180
then go from there
no
what happens to it then
you know that if you have a shape with 4 sides, and all of them touches the circle, then opposite angles add to 180?
you mean ?
you have 127 on the opposite side
yep
and since that whole angle is 105
you have the other side angle right?
now that angle is opposite to x
180-52
I see it now thanks
side question, where are you from cause i see the question is in malay
malaysia
3
i see
what about you
red arc = (127*2)°
blue arc = (105*2)°
overlap between the arcs = (red arc+blue arc) - (360°)
= 104°
x° = (1/2)(circle - (overlap arc))
x° = (1/2)(360° - (104°))
x° = 128°```
oh damn
thanks il look into this too
why do you add the red and the blue arc's
because if you add them it includes the overlap
and then if you subtract the circle you get only the overlap
because the overlap is counted twice when u add the red and blue
so when u subtract the circle its only counted once and nothing else is counted
so u get the overlap degree measure
what about the x calculation? I can't seem to be getting it especially about the 1/2
because if u look at the picture
x is inscribing the arc of the whole circle - the overlap
so it's 1/2 the arc measure of (whole circle - the overlap)
yhh I get the 1/2 thing
so basically I just find the overlap between the red and blue arcs because x = 1/2 (circle - overlap)
I see, thank you. Is this method useable in other questions with different amount of sides too?
alr thanks man I appreciate the assistance 
this is one of the hardest topic this year for me
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how to say if x and y are independent
@finite glen Has your question been resolved?
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@finite glen Has your question been resolved?
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solving expoential equations with no logs
$16^{-3r} = 16*4$
From there notice any common powers?
7aman
four
So simplify both sides in terms of base 4 and that'll solve for the exponent
so it's 4^-3r = 4?
$(4^2)^{-3r} = (4^2)*4$
7aman
This isn't exactly it. You can simplify both sides of the equation to a single term.
i got rid of 4^2 on both sides
Which leaves you with what for an equation?
-3r = 4?
and then i think i should do -4/3 as the final answer
You're comparing a power to an integer here
sure
What would it be
256
4^4
Right. So you can do the same with the left side and multiply the exponents together
So (4^2)^(-3r) would become?
(4^-5)^r?
It's a multiply sign
i see
mhm i get it
And then on the right, you can combine that into one term too
If we wanted to keep the powers
64
64=4^(?)
4^3
Narutoes
get rid of the fours
Well you said without logs, but in a normal situation, yeah
what do we do without logs
You can just set the exponents equal to each other since it is obvious they need to be equal since you have the same bases.
Basically the same as a log4 without calling it a log4
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can someone help me with this please (question b). I have repeatedly found that k = -3/2
this is my working:
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I need to solve the polynomial $z^2+(2-i)z-2i$
you dont know how to solve quadratics?
also z=0 is an obvious root here you dont need quad equation
you can factorize by z
right away
Dubs
Sorry typo
I reached $\frac{-(2-i) \pm \sqrt{3+4i}}{2}$
Dubs
how do i proceed from here?
why would you need to proceed?
,w z^2 +(2-i)z -2i
ok
maybe write 3+4i in exponential notation
so you can take the root
easily
im just double checkinh your calculations
please
I reached $\frac{-(2-i) \pm \sqrt{(2-i)^2 +8i}}{2}$
Dubs
I reached $\frac{-(2-i) \pm \sqrt{4-4i-1+8i}}{2}$
Dubs
I reached $\frac{-(2-i) \pm \sqrt{3+4i}{2}$
ok but i think exp notation is your only way out
but my textbook writes it soo trivially
letme show
Example 3 section 1.5 proves qudratic formula for complex coefficents
like inside root, it's of some square?
Wolfram Alpha doesn't understand your query!
Perhaps try rephrasing your question?
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,w 3+4i
ok it suckd
let me show the problem 21 they talking about
it's sort of mental trick it seems
3+4i= (a+ib)^2 they saying
(a+ib)^2 = (a^2-b^2) + 2ab i
yes
so if you have c+id
and want to find the sqrt
you want (a+ib)^2 = (a^2-b^2) + 2ab i = c+i d
so identify imaginary and real parts
so we look for two numbers a,b such that a^2-b^2 =c , 2ab=d?
yes
make sense
so for 3+4i
a=2, b=1 works
thus 2+i is a root
the other root is -(2+i)
yes, but If I'm just looking for the root of 3+4i
isn't it 2+i and -2-i ?
since (2+i)^2 = 3+4i, clearly 2+i is a root of 3+4i right?
I reached $\frac{-(2-i) \pm \sqrt{3+4i}}{2}$ = $\frac{-(2-i) \pm (2+i)}{2}$
Dubs
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I wanna oh
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6 questions to ask but same topic
Pure
so g(2) = 17?
yes
i got 49
Pure
17 times 3 is 51 then minus 2 is 7 squared
yes
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help
how do you find the turning point of a quadratic?
formula like -b/2a and Vertex y = b²-4ac/2a
bythe way what is the question about
I didint understand
who can help
me
start by finding the turning point
and then find a k
such that the turning point is on the y axis
meaning that its x cordinate is =0
and same for Q5 but the y cordinate= 0
@alpine sable
ok thanks
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https://gyazo.com/c3f831b5315e5708b658fcfe57ae5e34 how do i approach this?
@vivid roost Has your question been resolved?
<@&286206848099549185>
Hey!
hi 🙂
What math are you taking
this is stats and probability
okay thanks so much
ahhh
@vivid roost Has your question been resolved?
@vivid roost Has your question been resolved?
@vivid roost Has your question been resolved?
To find the expected value for the number of years of experience from the employees of this department, we will use the joint probability distribution given by $ f(x_i, y_j) $. The expected value of Y is computed as:
,tex $ E[Y] = \sum y_j f(x_i, y_j) $
kurenai_5h
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I need help with number 4
My teacher wants me to find 5 x's that would fit on that graph to graph the function
idk how to make the graph a triangle though
triangle? wym
-5
do -4 after that, and you should get your v
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how can i make this into a form that can utilize PFD
factor the denominator?
are you dealign with Laplace'a transformation to find orignal?
having trouble with that
$\frac{1}{s^{2}-4}=\frac{1}{\left( s-2 \right)\left( s+2 \right)}=\frac{1}{4}\left( \frac{1}{s-2} -\frac{1}{s+2}\right)\text{ then }\\\mathbb{L^{-1}}\left{F\left( s \right) \right}=\frac{1}{4}\left( e^{2t}-e^{-2t} \right)=\frac{1}{2}\sinh\left( 2t \right)$
Joanna Angel
first you introduce the image F(s) as a sum of partial fractions
and next you get the Lapalce'a tables
adn you read it from there
finally i noticed it can be exprfesed as hyperbolic sine
but it is makeup haha )
so optional thing
that's a difference of squares
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Hi, how can I begin to show if something like this converges?
I only know a few tests such as: finding the limit directly, ratio test (growth factor test), and the comparison test
oh and the sandwich theorem
but that isn't a test per say..
So, I am not sure how to show if this converges or not, although im almost certain it diverges?
this sequence is divergent, since its limit does not exist, becasue there are two subsequences convvergent to different limits
🙂
i am just wondering which two subsequences to take
think ab sin
am sure you know when sin = 0
and
sin = 1
or sin = -1
hence think , how to write n =
$sinx=0\Leftrightarrow x=k\pi$
Joanna Angel
okay that one makes sense
but im not sure how to pick another subsequence that doesn't just oscillate like the original one to be honest
just think about what n must be inside the sine for it to just stay there kPi
then
n = 12k
Yes
the subsequence converges to zero
Joanna Angel
n= 6 + 24k, i think
🙂
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How do I do this problem?
you need to use double integral
nd using iterated integrals
$\left| V \right|=\int_{0}^{2}dx\int_{2x}^{4}\left( x^{2}y+y^{2} \right)dy=...$
Joanna Angel
it is very easy to calculate
yw 🙂
I hate that the dx is there
@craggy briar Has your question been resolved?
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Flip 10 coins. What is the probability that there are an equal number of heads and tails or the first three flips are heads (or both)?
So the probability of equal number of heads is 252/2^10 which is C(10, 5) over total combinations of 10 coins flips
probability of first three flips being head is 1/2 * 1/2 * 1/2 = 1/8
so to get the probability i want i would subtract from 252 the values that are already considered by the 1/8 or the values that have first three head and equal number of heads and tails? so that would by C(7, 2) = 21. so the probability is either event is (252 - 21)/2^10 + 1/8????
@gilded galleon Has your question been resolved?
@gilded galleon Has your question been resolved?
I got the same answer with a slightly different argument, so I'm pretty sure you're right
@gilded galleon Has your question been resolved?
ok 👍
/close
!close
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How do I formally prove the 1st statement to be true.
I proved the 2nd statement to be false by counter example. It's when f(x) = x ** 2 and A = {1} and B = {-1}.
I tested empirically through python. It seems that the 1st statement might be True, but how do I formally prove it to be True
@knotty thunder Has your question been resolved?
pretty sure 1 is not true unless i'm misreading something big
can u give me a counter example?
# not one to one
def f(x):
return x**2
# one to one
def g(x):
return x + 1
A = {-2, -3, -5, 3, 4, 5, 6}
B = {-5, 2, 3, 4, 0, 1}
# {f(x):x∈A}△{f(x):x∈B} is a subset of {f(x):x∈A△B}
# {f(x):x∈A△B} is a subset of {f(x):x∈A}△{f(x):x∈B}
# not one to one
f_expression1 = {f(x) for x in A} ^ {f(x) for x in B}
f_expression2 = {f(x) for x in (A ^ B)}
# one to one
g_expression1 = {g(x) for x in A} ^ {g(x) for x in B}
g_expression2 = {g(x) for x in (A ^ B)}
print(f_expression1.issubset(f_expression2), g_expression1.issubset(g_expression2))
print(f_expression2.issubset(f_expression1), g_expression2.issubset(g_expression1))
this is my python code on trying to find counter examples of the problem
ok i might be mistreading something big lmao
oh jesus christ ok yes i did
the proof is like 2 lines
i read equality instead of subset -_-
just argue from the definition of subset and use properties of symmetric difference
hi can u give me ur proof? im still lost on wut to do lol
iknow the definition of a subset and symdi
but idk where to start
by definition of subset if A is a subset of B then every x in A is in B
so show that if x is the set on the left then it's in the set on the right, properties of symdiff will help
i guess contrapositive might be easier
hmm im still lost. wut properties of symdiff r u using. i only know the propert a ^b = (a-b) u (b-a)
specifically $x \in A \triangle B \Rightarrow x \notin A \cap B$
IV
you might even be able to exhaustively prove this
since either x in A or not in A and similarly x in B or not in B
you can brute force all 4 cases for all x for both sides 
sdjkahjkdashjk my brain broke down 😭
hmm wait
how about for when we input something lets say that is from A and B.
is f(A and B) ^ f( A and B ) going to be the subset of {f(x):x∈A△B}
your left hand set is empty, so yes
oh yea
hmm
so the statement is equivalent when is both true when the function is one to one
but if the f is not one to one
the 2nd statement is gonna go false
?
this is wut i get from trying to draw the sets and function on paper
idk how to formally write any proof
bijective function gives you equality
but if not bijective then it's a subset of
the start of the logic begins with:
if $x \in LHS$ then either $ x \in A$ or $x \in B$. Without loss of generality assume $x \in A$ (or otherwise swap A and B's), then $\nexists y \in B: f(y) = f(x)$ (why?)
IV
wait wut
but theres a case where y like that exists
if the function is not bijective
It's when f(x) = x ** 2 and A = {1} and B = {-1}.
i dont get it
wut u tryna say
sorry
can u explain a bit more
show that in this case x does not belong to LHS
that requires some amount of thought instead of straight up copying down properties
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I need to help with this question. I need to find the reading of the voltmeter and the ammeter right after the switch is closed and after a long time, but I'm not really sure what to do with she solenoid and the capacitor
can anyone give me hints with what to do with those two?
All are uhh ideal voltmeters and ammeters?
yes
just Henry? in 10^-3
?
yeah
from what i assume, at the estart i can just assume this as one single series circuit?
because the loop witht he inductor will not flow any current, and the one with v4 will also not flow, because the one with the capacitor provides almost no resistance
so it'll just be strictly flowing through in one single loop right after switch is turned on?
so v2 = v3 = v4 = 0
am i right so far?
so V1 is just 40V, cuz that's the only resistor in the circuit
but what is V5, is it also 0, or is it at 40
cuz isn't the voltage through a capacitor like, 0 immediately after the switch is turned on?
so V2 ~ V5 = 0 immeidately after, and V1 = 40
how the bound differs from the constraint function? And how does it affect the solution
hey not to be that guy but i'm using this channel btw
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And then after a long time, the loop with capacitor is dead, the inductor just acts as a wire, so now its a parallel circuit?
so overall resistance is 50 + 100/3, so the current is I = 40/(250/3) = 0.48A
so V2 = V5 = 0
V1 = IR = 0.48(50) = 24V
and the voltage across both V3 and V4 is equal cuz they are in parallel, so its just 16V?
<@&286206848099549185> anyone?
so to summarize for what i got
Right after switch is closed
V1: 40
V2 = V3 = V4 = V5 = 0
After long time
V1 = 24
V2 = V5 = 0
V3 = V4 = 16
So in terms of current, at the start, there's none through A2 and A3 so that's 0
A1 and A4 is equal cuz its current in a series circuit, so its just 40/50 = 0.8A
And then after long time, A4 is 0 cuz capacitor is fully charged
A1 is 0.48 cuz of this
and because the resistors are 2:1, A2 = 0.16A and A3 = 0.32A
Did i do this correctly? anyone?
is the angular frequency (w) given in the question??
or frequency (f) given?
???
Basically what happens is that when the switch is closed immediately, the current through inductor(solenoid) will be zero, as the nature of the inductor is to oppose the current, so, v2=v3=0 when switch is immediately closed.
Capacitor will start charging and hence current will flow in capacitor
after a long time at t=infinity, no current will flow in capacitor and current will flow in the branch having the solenoid. SO, V5=0 when t=infinity.
now after eliminating the elements according to the condition, we can find the ratio of impedences and hence current in each branch, for that we need frequency in order to find the impedence of the elements like capacitor and inductors,,.....
in order to find the Xl and Xc( impedences of inductor and capacitor respectively), we need frequency as
Xl=wl and Xc=1/wc where , w=2pif
i feel like you are way overcomplicating this for my class
Well i ain't aware of the class you are present in, but i guess we cannot solve circuits having inductors or capacitors without the frequency of the circuit, as impedence cannot be found.
hmm
alright
also another question
if a current is decreasing at a constant rate, and that rate is di/dt = -0.018A/s
do i treat that as negative or positive
like, its decreasing, but the rate is negative?
I guess u are talking about the inductor, the negative sign just denotes that the current is decreasing, so you will use negative sign while solving the equations.
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I was doing this question earlier and I got three parts wrong, and I'm not sure where I got it wrong, so can someone check for me?
I had to find the values of the voltmeter and the ammeter right after the switch is turned on, and after the long time
here's my answers
Voltmeter at the start
V1 = 40V
V2 = V3 = V4 = V5 = 0V
After long time
V1 = 24V
V2 = V5 = 0V
V3 = V4 = 16V
Ammeter at the start
A1 = A3 = 0.8A
A2 = A4 = 0A
After long time
A1 = 0.48A
A2 = 0.16A
A3 = 0.32A
A4 = 0A
all my logic is here if you want to see wehre I went wrong
🙏
ok i realized two of my mistakes. i calculated A3 = 0A and A4 = 0.8A but i put my answers in wrong
The only other thing that i think could be wrong is V5 = 0
It seems to be question of physics 
cuz i thought it could be 40V, but i thought at the start, voltage through capacitance was 0
yeahhh, but i was told i can ask physics questions cuz physica is technically math :3
nvm
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please can anyonje help me?
@alpine sable Has your question been resolved?
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4(x+1) + |x+4| < 2(2x+3)
Hello. Can someone help me with something?
I have this inequality and the exercise requests me to verify if 0 is a solution of the inequality
but I don't really understand
replace x by 0, check if the statement you get is true
so 4(0+1) + |x+4| < 2(2 * 0 + 3)
4 + 4 < 0 + 6
8 < 6
nonoo
4 + | 0 + 4 | < 6
| 0 + 4 | < 2
-2 < 4 < 2
it doesn't maky any sense
am I wrong somewhere?
no, you're not wrong
Remember, i asked you to check IF the statement is true
as the same as the question
so is the statement true or false?
so 0 can't be a solution because the " -2 < 4 < 2 " is false
so the whole statement is false
It was already finished here btw
if I have absolute value don't I need to use the opposite of the number in the right in the left of the inequality?
...that might be the correct thing to do in some circumstances but it's not something that a law of the universe requires you to do any time an absolute value exists anywhere
it is true that if x=0, then 4(x+1) + |x+4| = 8 and 2(2x+3) = 6, and so the statement 4(x+1) + |x+4| < 2(2x+3) is equivalent to the statement 8 < 6
soo... How can a stupid like me find if I need to use that "law"
Overall, the statement is false, at least I understood that
...well it's just also true that |x| < y is the same as -y < x < y
so if you're trying to work out which x satisfy |x| < 4, turning that into "-4 < x < 4" is probably useful
if you want to know if |4| < 6, you can turn that into "-6 < 4 < 6" because it's still true that those are the same, but just computing that |4| = 4 so the statement is 4 < 6 is also valid
in general there isn't really ever only one way to solve something, any sequence of valid inferences will get you a correct answer
Thank you for the explanation and for your time! I really appreciate. I was a bit confused.
we can call this an "ugly" math problem, ig...
...?
i don't see what's "ugly" about it
I usually call a problem "ugly" when I can't do it by myself, hehe, I am a strange person. However, even with the inegality resolved wrong, I still got the same answer.
idk what you mean by "resolved wrong"
you did it two different ways and both of them were correct
oh, I thought that without using this law isn't as correct as it is using it
Anyway. Thank you very much for your time! Have a great day!
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hello, i saw a correction of an exam and at some point they give this equation
e^(1/α -1) = -α/(α - 1 )
α range is between 0.21 and 0.22 that make both left and right sides positive but how did they went from left side to the right side
e^x is approximately 1+x, that's prolly what they did
is it $e^{\frac{1}{a-1}}$ or $e^{\frac1a -1}$ ?
aPlatypus
@novel widget
$e^{\frac{1}{a-1}} \approx 1 + \frac{1}{a-1} = \frac{a}{a-1}$
aPlatypus
I don't really see how they got their minus then
α is ranged between 0.21 and 0.21
α -1 is negative while exponential is positive
i think the equation is incorrect
this is really missed up ngl
well it's not the first nor the last typo we'll ever do
yeah i guess i will just ignore it for now, thanks
how can i close thi
s
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A
Here’s what my teacher did
Step 2, x^-1 * x should be 1
Numerator, when he multiples xy why is it not xy^3+y^2
I know what it should be but I don’t understand why
negative exponent or 1/x
Mhm
And now if you multiply x
x/x=?
Another way to look at it would be that
x^-1 * x^1 = x^(-1+1) (why?)
Np
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i am investigating behaviour of nested functions of cosine
i know that dottie number is what $$\cos^{(\infty)}(x)$$ stabilizes to (where $f^{(n)} = \underbrace{f(f(\cdots(}_{n \text{ times}}x)$) )
artemetra
this is equivalent to what the sequence $a_n = \cos(a_{n-1})$ converges to
artemetra
this function becomes a straight line
but
let's analyze $\cos^{(\infty)}(bx)$
$x$ is the variable, $b \in \bR$ is a parameter
dottie number is the case b=1
however, this function behaves very weirdly for different values of b
how/where can i study this weird behaviour?
ofc what i have here is an approximation because i have the function nested finitely many times
(although 70 times is a pretty good approximation)
the x/b argument is to keep the period of the function the same
@exotic canopy Has your question been resolved?
Study as in? Its properties?
Well a good start is its fixed points
And to test if they r there u can use that banach point theorem
Taylor expansions, de movieres generalization, stability for different number systems, just to name a few
Also if u know how to (me also researching this topic so don't ask me how( u can design a differential equation if there exists one
@exotic canopy
i see
it's just really difficult cuz these numbers are all transcendental
hm
,w taylor expansion of cos(cos(x))
bruh
Eh Taylor might be stupid. Wait no it is stupid
I suppose Fourier series would be...shittier
Hmm perhaps a slope field? It would be the slope field of y' = cos(by)
Because aPlaytpus and my research have told me that a_n = f(a_(n-1)) and, y' = f(y) are similar
So if u study one, the other will have similar properties
Also u would wanna know whether ur parameterized function cares about a_0
I think the graph can help with that
that's true
wdym?
Well when b=1 we know the sequence converges to a single value, no matter what a_0 (ie first value) u take. Does ur modified sequence show that too?
The word is constriction, I think
I just realised this is equivalent to checking for banach fixed point theorems validity on ur modified sequence
hm
oo i'll look into that
Is that a yes, a mhm, or a hmm?
the last one
I see
the answer is kinda
it's periodic
it doesn't converge to one value
but it converges to one interval
This weird expression of taking cos over and over again is just a sequence x_n=cos(x_{n-1}). There is a very cool theorem called the Banach Fixed Point Theorem that let's figure out the limit of sequences like this and depends on cos(x) being a so called contractible mapping.
Check out my MATH MERCH line in collaboration with Beautiful Equatio...
This very briefly covers the banach fixed pt theorem
And studies ur sequence for b=1
yeah i know it's properties for b=1
it's just that the way this function changes over b
Eh? I think as n approaches infinity it becomes denser so it ends up approaching a value just above 0.5
Changes over b...partial differentiation

this kinda reminds me of logistic map for some reason
Isn't that for like exponentials
And that reminds me u can even use the imaginary definition of cosine here, see if it gives something interesting
Well I don't know much about it, just heard that it's connected to a variety of phenomenon
oooo right right
wait
$\cos(\theta) = \frac{e^{i\theta}+e^{-i\theta}}{2}$
artemetra
artemetra
$\cos(\cos(\theta)) = \frac{e^{i(\frac{e^{i\theta}+e^{-i\theta}}{2})}+e^{-i(\frac{e^{i\theta}+e^{-i\theta}}{2})}}{2}$
artemetra
thanks bro
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I need help solving this question. I got no clue how to solve it
i dont know how i can decide on the third length of a triangle
Triangle inequality
Sum of 2 sides has to be greater than the third
Can't be equal
so the third side should be less than 6+4?
yeah
that means it cannot be 2 yes?
yep
and this is called triangle inequality?
difference of two sides must be less than the third side?
yes
lemme check if its correct on the answer sheet rq
alright nice
thank you grey
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if i have
4h/9/h
can I eliminate the h?
yes
$\frac{4h}{\frac{9}{h}}$?
artemetra
no
this?
4h/9/h/1 i think
can i ask another quick question
if i want to change them to multiply
4/h * h/1 is that possible right?
can you explain me why they can cancel out?
imagine the 5 wasn't there
$\frac{4h}{h}$
artemetra
thanks ❤️
wdym?
there is something that mathematician do
is pass double fraction to multiply one fraction with the other one
i dont know how is that named
you mean like $\frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \cdot \frac{d}{c}$?
no i mean
You can think about it as
$$(4h \over 5) \over h$$
$$\frac{4h}{5}\over h$$
$$\frac{4h}{5}\times \frac1{h}$$
artemetra
this?
no problem
seeinglike this i can eliminate the h without remorse
hahaha
well thank and happy december first
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✅
the thing is i need to eliminate the h
Not really possible here, you're going to have at least one h remaining
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can someone explain this?
if you expand it entirely there will be some zeroes after 7 like 14670000000000000..
oh my god 😭
[
1467 \cd 10^{?}
]
what is ?
99?
yeah
so
how many zeros
OHHH
99 ZEROS?
yes
bro my dumbass thought i had to write down 99 zeros
in the qn

thank you so much'!
is this correct
and how do we simplify fully btww
okay
one big question
did you write [
\s[3]{\f62} \tss{or} \f{\s[3]6}2
]
both 😭
this
and this
what u wrote doesnt really show it well
you have to be clear
they are very different
for [
2p^{\f13} = 6
]
what is the step you do?
yeah now this is correct
this is wrong
what u wrote
but anyways
like
is it correct if the qn asked for indices? just wondering
[
\p{abc}^n = a^n\cd b^n\cd c^n
]
