#help-0
1 messages · Page 561 of 1
?
No
negative times negative is positive tho
This isn’t times
thats true
they're talking to soso/ directing it at them
^
What’s the actual answer
ok idk sorry
,w calc -3/12 - 8/12
you still need help on this?
@cinder lily #prealg-and-algebra
oh ok
ok the planet addition problem isn't too bad i think you just need to use logic and the given information to figure stuff out
sure, im doing other stuff rn tho, was gonna come back to it later
Hey anyone able to help me?
dont ask to ask
Can use e^(ax) grows faster than x^b (for a>0) so the limit is 0. (can be proven using L’Hopitals a bunch of times)
(Since e^(-5x)=1/e^(5x))
Hello
hi

How do i distributive property for (x + 3)
distribute the negative
How
-(x+3)=-x-3
yes
Thanks
So should the negative still be there?
Or since I used it, it should be gone now right?
you distributed the negative, you don't put another negative around the parenthesis after it's been distributed
So it is good right?
so you should get (6x-15)+(-x-3)=(2x+2)+4
Why would we substitute with a +?
this implies the two things are being multiplied, they should be added
if you write (a)(b) it means a times b
that's not what we want
what's just a law in math
this is just notation
Yeah but how can we just add a + in the middle
I’ll just trust you
adding a negative is the same as subtracting
Alright
you don't need to write it as +(-x-3) only do that if you find it helpful
you can get rid of the parenthesis after you distribute
6x-15 -x-3 = 2x+2 +4
now just collect like terms and solve
1. 1 23 24
2. 1 23 24
3. 1 23 24 14
4. 1 23 10
5. 1 23 10
6. 1 23 10
7. 1 23 24 10
8. 1 23 10
9. 1 23 10
10. 22 26 28 18 14
11. 16 26
12. 16 12 24
13. 16 12
14. 16 12 24
15. 1 23 24
16. 1 23 24
17. 1 23 24
18. 1 23 24
19. 28 12
20. 14
21. 6 24
22. 6 24
23. 6 24 18 12 21
24. 6 24
25. 6 24
26. 6 24
27. 6 24
28. 21
29. 25
What do you see? Do you see any pattern?
@worthy crest Please don't send the same question to multiple channels.
i just tried doing this, but the something seems off. https://docs.google.com/document/d/1QSpO1tAHDxnmPDpqqXfeC_GNQWs15jTLbknm3V6L5eU/edit?usp=sharing
T = cannot be 4 H = 5 E = 5 A = R = cannot be 4 V = N = 1 U = 3 S = 2 P = S and U have a sum with the integer E at the end. Assuming S = 9 and U = 8, their sum will have a sum of 17, and since there is a number carried over, then we know that N = 1 because the largest possible values will n...
i may have made a silly mistake though
its not complete btw i stopped once i got E = H = 5, which doesnt make sense
read about the secant-secant theorem and #❓how-to-get-help @worthy crest
what does that even mean
i take that back nitezba, i think it should be done from left to right since numbers are being carried
I just don't know where to start. Can someone explain the steps please?
What is normal form?
a line has 180 degrees
you could do this multiple ways, its really simple and straight foward do you have any notes or anything
We just started this today
Not that i remember
when a line cuts through two parallel lines (idk the word like bisect or something? idk) angles have a bunch of congruencies
he has a really strong accent so its sometimes hard to understand him
the y=100 is the same angle as u, v, and s because of exterior angles theorem, and like 2 others
i dont know the formal names of hte theorems i just know them
Parallel lines are important when you study quadrilaterals because six of the seven types of quadrilaterals (all of them except the kite) contain parallel lines. The eight angles formed by parallel lines and a transversal are either congruent or supplementary. Check out the above figure which shows three lines that kind of resemble a giant […]
here
so like
this is better ig
if i have this information
and i pick a random 3 digit code
how do i figure out all of the different combinations of letters?
e.g. 789 - combinations would be ptw, ptx etc
@charred heron Take the cartesian product.
i do not know what that is
Well, let's say I have two sets: {a, b} and {c, d}. The cartesian product is all the 2-tuples where the first element is from the first set and the second element is from the second set: {(a, c), (a, d), (b, c), (b, d)}.
You can do a cartesian product with three sets as well, which is what you'd do.
Is this just to list them by hand or to make a program?
make program
Then you have something like:```
let set1 = "abc"
let set2 = "ghi"
let set3 = "tuv"
let results = {}
for (character m in set1) {
for (character n in set2) {
for (character o in set3) {
results.add(m + n + o)
}
}
}
It'll fill up results with all the "words".
if we let n=3 for a sec
1/1 + 1/2 + 1/3 + 1/(1+2) + 1/(1+3) + 1/(2+3) + 1/(1+2+3)
whats the sum notation for something like that
doe stha texist
so i want to calculate for n something like this
@waxen tartan Maybe this: $$\sum_{S \in \frak{P}( {x: x \in \mathbb{N}, 1 \le x \le n } ) } \left( \frac{1}{\sum\limits_{s \in S} s} \right)$$
Chai T. Rex
thanks!
No problem.
just wondering what's the \frak {P}
It's the powerset function.
ahh
Today my teacher went over this problem and I really didn't understand her- x^2=16 she said that the 4 could be positive or negative? How does that work
x^2=16
sorry
Chai T. Rex
No problem.
don't ping helpers immediately
pythag
oh i didnt see the lack of a 15 minute wait

levi, please read the #rules and #❓how-to-get-help
I already read
then follow the rules
Ok
thats why they exist...
can I get help now
you already got help
pythag
pythagorean if you need a further hint
Idk how to use it
ok well what does pythagorean say?
A2 + b2 = c2
Right triangle
The angles
no
Uh the sides of the triangle
Ikr
yes, which side is c?
the hypotenuse or a leg? (legs are the sides which form the right angle)
Legs because 36 is already hypotenuse because it’s longest side
c is the hypotenuse
well you have the hypotenuse and a leg, and want the other leg
so plug in the values and solve for the other leg
33 squared plus 36 squared = c2?

so c is given
so given you have the c value, your application of pythag shouldnt be to find c
What is C then
here
the hypotenuse
it's 36, the longest side as you said
So I don’t have a B ?
yes
you dont have one of the legs
so pick your favourite letter to solve for out of a and b 
@runic vine Well, there are three right triangles in that image. Which has two known sides?
Well, the three right triangles are FGH, FEH, and EGH.
Do you see how those are all right triangles?
Yes
OK, which of those three triangles has two known sides?
EGH?
Right, now if you have two sides of a right triangle, how can you get the third side?
Aight
So, find the third side and write it in.
We have a and B right ; so it’s just C we need to find
41?
40?
Yes, that's right.
Now, fill that in for GH on your drawing and then what triangle now has two known sides?
FGh
2 leg
OK, is 40 across from the right angle or next to it?
Next to it
OK, is 85 across from the right angle or next to it?
It’s above it
Right, it's across the triangle from it.
So, that's the hypotenuse.
So, we put the leg on the addition side and the hypotenuse on the length by itself side.
What equation do we have for the Pythagorean theorem?
OK, did you understand how I found out which side was a leg and which a hypotenuse?
yes
Chai T. Rex
yes
The two legs are on the side with the plus.
The hypotenuse is on the side without a plus.
Does that make sense?
Yes
jacob went to his girlfriends house at 3:10pm. he got home at 12:40am when he got home he got on his pc and stayed on to play with brad angad and nathan until 7am. how long did he spend at his girlfriends house and how long did he play on the pc for. what grade is this?
@runic vine OK, so fill in 40 and 85 to the formula and show me what you have right after you fill them in.
@solar sierra Sorry, busy. #help-9 is open if you hurry.
Okay so 40^2 + 85^2 = c^2 ?
No, remember 85 is the hypotenuse, right?
Yes, that's right.
You put the hypotenuse on the side without the plus.
OK, now find b.
75
It was FH and 75 was the answer
Right, and that's the answer to your problem.
Thank you!
You're welcome.
im stumped for this one
@shy prairie OK, division is the outermost operation there. What's division convert to in a logarithm?
subtraction?
Chai T. Rex
Let's do the first log. What happens when you take the logarithm of a number to a power?
err doing -8^5 wouldnt b correct right
No, not exactly.
Chai T. Rex
The power comes out to multiply it by the log of the the base number.
Chai T. Rex
5logc?
1/2logx
Chai T. Rex
1/3logab?
No, don't do the part under the square root yet. Leave that inside the logarithm. What do you take out of the logarithm when you have a logarithm of a square root?
err wat exactly do u mean by taht
Well, you took out 1/2, right?
here
Chai T. Rex
Chai T. Rex
Does that make sense?
Chai T. Rex
Yeah, it sort of works like that.
The whole thing is inside the square root, so it's treated as one together thing.
Now, inside the second log, we have a multiplication.
What does log change multiplication to?
addition?
3logb
Chai T. Rex
oh so u just plug it in now?
Chai T. Rex
So, what do you get as the answer?
-31
oh oof lemme see wat i did wrong
Bah.
You're welcome.
abe
Are you helping someone at the moment
what am i supposed to find when i plug in n=1
this is for an induction question btw
Just sub in where there is n and see if the trivial case holds
yes but what is the LHS when n=1
E.g, show 2n is always even, we take the trivial case n=1, then we have 2n=2(1) = 2 which holds true
i've only given u LHS
i know how induction works
i don't understand how this series works
if it's for an induction question, you'd need what you're trying to prove the sum equals
sum the squares of natural numbers from 1 to 2n
Its jst a sum of the natural numbers squared
$\sum_{i=1}^{2n}i^2$
moshill1
yeah so i get LHS=1?
yes
you also havent given a RHS, so im taking your word for it
$\frac{n(2n+1)(4n+1)}{3}$
abe
if you sub 1 here
wait no sorry
and u get 5
if you sub n=1 to the LHS it's 1+2^2
so 5=5
why is it 1^2+2^2
so n=1 is true
$\sum_{i=1}^{2(1)}i^2$
moshill1
$\sum_{i=1}^{n}i^2 + \sum_{i=1}^{n}i^2$
abe
that?
no
sum from i=1 to i=2n, but n=1 so 2n = 2
so sum i^2 from i=1 to 2
(1)^2+(2)^2
im still confused a little
is it something to do with how there are 2n terms instead of n terms
so S_1 would be 1^2+2^2
So you need to start at 1
Till yo get to 2^2
So thats just 1^2 + 2^2. =5
As for the RHS, its easy you see that when you place in n=1, you get 5
Just basic arithmetic
ye thats why i was only asking for LHS
So now you have 5=5
any way to explain without using sigma concept
or not really
cuz i kinda get it
with sigma
how would you explain this to someone who has never done sigma sum stuff
I meqn sigma is just a way of shortening how much you write
Like instead of saying $ 1+2+3+....+n-1+n$, we say $\sum_{i=1}^{n} i$, which is just much shorter to write
Conor Sheridan
sum until the nth even natural number
Yeah, so your last term is 2n
So the top of the sigma, we put 2n
And then each value is squared
So we put i^2
ok
Giving us $\sum_{i=1}^{2n}i^2$
Conor Sheridan
Reading it takes a lil bit of time but it becomes easy
The bottom is where we start
The top is where we finish
rip this is a misunderstanding
The stuff to the right of the sigma is whar we are doing to each term
i already know how sigma work
Oh lol
ye
@thorn kindle The i here is an index, not the imaginary number
I can let it be q if that helps lol
mathematics (mathematicians) have weird norms
Amd pulling moves on me
I dont have to try 😎
😭
You need the dollar sign to begin and another at the end to end the latex @signal wolf
$\int [0,2] ln x^x^2 dx$
MrThink15000
$\int [0,2] ln x^x^2 dx$
```Compilation error:```! Double superscript.
l.55 $\int [0,2] ln x^x^
2 dx$
I treat `x^1^2' essentially like `x^1{}^2'.
Preview: Tightpage -1310720 -1310720 1310720 1310720
[1{/usr/local/texlive/2020/texmf-var/fonts/map/pdftex/updmap/pdftex.map}]
(./757639076475174922.aux) )
Here is how much of TeX's memory you used:
18264 strings out of 479485
359566 string characters out of 5871962```
I assume you mean this
$\int_0^2 ln(x^{x^2}) , dx = \int_0^2(x^2)ln(x) , dx$, then try let u be something
Thx bro : D
Conor Sheridan
No bother, in integral, the bounds are done using the _ and ^
Log laws then probably u sub
Yeah
$\int_0^2 ln(x^{x^2}) , dx = \int_0^2(x^2)ln(x) , dx$, then try let u be something
Conor Sheridan
why does $20^20 = 5^20*2^40$
Kathullhu
$\int_0^2 ln(x^{x^2}) , dx = 8/9(ln(8)-1)$
MrThink15000
why does $20^{20}= (5^{20})(2^{40})$ ? Is this what you wanted?
Conor Sheridan
yuh
uhh can someone help me
$8/9(ln(8)-1)$
MrThink15000
don't you use the distributive property
@fleet steeple why does $20^{20}= ((4)(5))^{20} = (5^{20})(4^{20}) = (5^{20})(2^{2(20)}) = (5^{20})(2^{40})$
index laws
Conor Sheridan
hi
What is each value increasing by as we increase x?
I was helping someone else
its increasing by cubes?
I was hoping he/she would have answered it lol
ah
btw conor
do u know how to factor a non monic
cubic
$8k^3+30k^2+37k+15$
how to factor
abe
first off k=-1 zeroes out, so you have (k+1) as a factor
factoring is mostly guesswork
educated guesswork
it should involve factors of 15 i think
etc
so you'
to be more precise, factors of 15/8 can be roots
what how
including negatives
that's the rational root theorem
divide the coefficient of the constant by the coefficient of the highest degree term
actually wait i stand corrected
factors of the coefficient of the constant
divide them?
CST
yes
and 8 has factors $\pm 1, \pm 2, \pm 4, \pm 8$
CST
yes
actually i should insert descartes' rule of signs here
to show that there can be no positive roots
essentially you observe the sign changes in the equation
anyway, trying out smaller values to factor easily helps
again, -1 zeroes out and is thus a root
and then you can factor out (k+1)
leaving $8k^2+22k+15$
CST
are these all direct proportions?
huh, i think your teacher's crazy lol
especially for #12
lol these problems are extremely scary
hints:
7 is close to 8
14 and 26 are even
159 is 10 more than 149
everything besides #13 isn't proportions
they're like riddles
well in that case any answer for any problem is justified
secret operation or smth
for example #11 could be 8 since you divide the first term by 13 and add 3
you have to add the rule of "find the relation of adding/multiplying/dividing that is the simplest"
I'd still say that's not well defined
find the best alternative is very vague lol
ehhh they're pretty unique given the multiple choice part
I hate teachers who write "find the best answer" and sabotage their multiple choice so all the choices are wrong
I did the explanation
what if someone comes up with a slick relationship that fits but the person who wrote the problem wasn't thinking of that

14 is 15
15 is 268
They all have the logical formulas lol
They are like riddled
Riddles
Ten is obviously four.
$\int_1^2 {x f'(g(x))dx}$
Josh.
can someone help me solve this integral with the given info
Yup I could not find a mental ability server so...
reverse chain rule
I think the answer to 11 is 9 because in my opinion the rule is take the first digit and add 3 to it
no idea how to do that
the integral of g' * f'(g(x)) is f
and here you have g' outside because x is close to the derivative of 5-x^2
Ok
uhh
I was making fun of the nature of the problem actually
don't take that as serious advice
eh just trust me on that rule then
it's fine to use if you've learned the chain rule
wait figured it out
i just set g(x) = u
so u = 5 - x^2
du = =-2xdx
-1/2du = xdx
replaced xdx with du
looks good
yeee
I forgot it's more known as u-substitution haha
thank you very much
let me see
my teacher just posted these problems in the middle of doing matrices
oh
welcome
@alpine sable do you have any other practice problems of such nature
that you'd be willing to share
also, if anyone could help with this it would be really appreciated
I missed the lesson because I was at the hospital today, can somebody help me with this?
quadratic equations have the form ax^2+bx+c
in this one you have b = 4, a = 1
so therefore -b/2a = -(4)/2(1)
then input that value into the function to find y vertex
other part seems self explanatory
This one??
I’m not sure tho, but that’s how i do it
Did your teacher mention about what she is asking for?
$\ln(\ln(x)) = 2 \to e^{e^2} = x$
bunny
the first side is just a constant use a calculator
he, and nah
yeah prettys approach looks right
combine the logs and cancel then simplify however you like after that
Can someone explain me this?
@alpine sable still here?
Yes
i'm a little confused at the wording of the problem as it seems a little redundant.
you say f'(x) ≤ 8, but then you say f'(x) ≤ 3 for all x?
either the latter implies the former, or there's a typo somewhere.
It’s both
but why would you state both
if f'(x) ≤ 3 then it's guaranteed that f'(x) ≤ 8 too
are you absolutely sure you copied everything 100% correctly with no typos?
No I made a error
see, that's what i'm trying to get at
Sorry let me write it again
yes, please do that.
,rccw
Yes
ok
so you're asked to sort those statements into "guaranteed", "possible" and "impossible"
Yes
ok, progress so far?
are you familiar with the concept of increasing and decreasing functions?
you might do well to try and visualize what the graph of y = f(x) looks like under the conditions that they state
Yes
so given that f'(x) ≤ -3 everywhere, what can you say about f?
It’s the derivative of f(x)?
???
read my question again please
so given that f'(x) ≤ -3 everywhere, what can you say about f?
what can you say about f itself?
what property does it have that will significantly simplify matters here?
I don’t understand, like is it less than -3?
look i even prompted you with "increasing and decreasing functions"
the derivative of your function is bounded above by -3.
in particular this implies that the derivative of your function is negative.
now what do we know about functions whose derivatives are negative?
It’s decreasing?
Never mind
This function is decreasing right??
yes i literally told you
your function's derivative is negative
therefore the function itself is decreasing
Yes, I understood that part
if you did you wouldn't have asked me about it again
Sorry I’m a bit confused on this topic
this function is decreasing
Yes I get that
if we have a decreasing function on some interval, at what point does it achieve its maximum on the interval?
At -infinity?
on some interval
i didn't say "the whole number line"
i meant a closed interval to be more specific
[a,b]
Ahhh ok
we have a decreasing function defined on [a,b]. where does it achieve its maximum?
0?
Then how do we achieve its maximum??
It helps if you visualize it in your head
yeah, imagine a graph of a decreasing function, over an interval
Can be as simple as y=-x if you want
ayewaddup do you want to take this over
It’s like this right??
this graph could use some more labels but yes
Uh lemme see the question Rq
Gracias
no
And these statements are all noted down correct?
Yes
Sorry this Channel is busy
It’s just that it says f’(8) is less than 8 and also less than 3 in the next line
No don’t mind that part
she updated the statement in the second ss
okay ann pretty much gave you part a
It would have to be guaranteed
Yes
Okay so
Hold on I’m tryna
Okay so f’(x) <= -3 right?
Yea
And the derivative tells us by what degree the function changes at every point
Or in other words the slope of the tangent line at every point
Now if the slope of the tangent line is always lower than -3
Can we agree that the slope is always negative?
Channel taken
Good
Now it’s forget about that for a second
Say I have another decreasing function
Like y = -x^3
Sorry channel is taken you’re going to have to wait for one to be free
hes also taking an exam so thats very against the rules
Yes
3
And why do you say this?
Because i think it’s the highest point on the graph
Let’s take another example
Say y = -x
Same interval
Is it increasing or decreasing
-3 ?
And why do you say this
Because the function is decreasing and the maximum should be negative?
Think about it this way
If a function is decreasing right
That means as you go to the right, it will go downward
Yes
It goes up
The function is going right and it’s negative and it’s going downwards
yo i have a question
Ask in a free channel
kk
Better but I think you’ve gotten the conceptualization aspect so I won’t push it
Now for y = -x^3
On [-3, 3]
At what x does it reach its maximum
-3
Yes
And that means no matter what -3, our lower bound, is our maximum
That’s gonna be the conclusion we use for a
Yes I got it now
With that knowledge explain to me why a is guaranteed
The function is increasing since its positive
why is it increasing?
5 is the maximum value
Because it’s positive?
What is positive
Oh wait, so they alr gave the absolute max
The min and max don’t matter yet
You need to classify whether the function is increasing or decreasing
How do we draw a graph for this tho?
Do we need a graph?
We need it to determine whether it’s going upwards or downwards?
What’s the first derivative of y = -x
-1?
Good
just ask dont ask to ask
And -x^3?
-3x^2?
Negative
So do you see how when our first derivative is always negative
Our function is decreasing?
Yes
Yeah
Which means it will always be a negative number
Yeah
So yeah decreasing
And what did we say about decreasing functions on certain intervals?
It would be Guaranteed?
Yes
1
And what’s f(1)
8
So is 8 the absolute max?
Yes
Now b
If f(x) = 0 at two different x’s
It requires the graph to pass through the x axis and then come back up again
Implying that at some point we have a relative maxima or minima
Or the derivative = 0
Is this possible?
If so is it guaranteed?
Sorry I have to sleep
No it’s not possible right?
Yes I got it now!
I’ll leave you with this
If f’(x) at its highest can be -3
That means atmost f(x) is linear
Just see if those points fall on or below the line
If above it’s not possible
If below it is
Gn!!
you can take their difference, whichever way you want, and check if it's positive or negative in your interval
and if it's negative, multiply it by -1 before proceeding
In 40° right triangle, apply TOA to find the value of opposite having 12m adjacent
a. 10.06
b. 10.05
c. 10.04
d. 10.07
can someone help me rn
btw this is not an exam
its a homework but multiple choiceses
im having some trouble
i tried to answer it but i got 90.09m
one moment
@foggy onyx so how exactly did you get 90.09 m?
it doesn't look like it comes from a degree vs radian mode mishap
i used toa elevation formula
"toa elevation formula"?
Angle of Elevation TOA
Angle of Depression TOA
but since its finding the opposite i used the elevation one
no we don't give out answers
is TOA the trig memorization thing?
i don't know what elevation or depression you're talking about when all you have is A SINGLE RIGHT TRIANGLE
x/12 = tan(40°)
i see no need for this overcomplication with "angle of elevation" vs "angle of depression" which really only make sense when you're considering like... lines of sight in a "physical" setting
okay okay
and even then the only difference is in how the relevant triangle is positioned
so whats the answer
no i'm not telling you the answer
;-;
...
and tan(40°) isn't even 1.32 so your calculator IS in radian mode when it should be degrees
tan = opp/adj.
your adjacent is 12
your opposite is x
tan(40°) = x/12
this does NOT give tan(40°)*x = 12.
OOPS OMG YES
just like z/4 = 5 does not give 4 = z*5
I DIDNT NOTICE LOL SORRY
THIS IS WHAT IVE BEEN TRYING TO POINT OUT
??
can you use your calculator right now and tell me what you get when you calculate 12 * tan(40)
in DEGREE mode mind you
e
bruh
im really confused
;-;
tan(40)*12 = x
and then IMMEDIATELY AFTERWARDS
turn that multiplication magically into a division
im shorcutting it..
no you're not
you literally took a multiplication symbol and replaced it with a division
do you even algebra
dont notice the writting
do you even algebra
They are doing a different problem
it's no use giving you formulas when you're shaky with your algebra
you seem to like. not understand what you're doing algebraically
and i'm not in the right headspace to clear that up rn
I KNOW HOW TO SOLVE I JUST HAVING A HARD TIME ON THE FORMULA
YOU LITERALLY TURNED X = 12TAN(40) INTO X = TAN(40)/12 AND CALLED IT "SHORTCUTTING"
i even told you this
but no
He’s blindly following the example
Just multiply tan40*12
the location of you values changes depending on the question
start with soh-cah-toa
the rest is algebraic manipulation
prettygirl i already told him to do that but he chose to ignore me
or just not read the message
or maybe it wasnt a conscious choice
okay
but still
IM SO SORRY FOR DISTURBING YALL OMG LMAO
but though thanks
,calc 12 * tan(40*pi/180)
Result:
10.069195574127
Yes by rounding it would be that
10.069 rounds to 10.07
so 10.07?
Yes
I think you can do the Pythagorean theorem from here
To get the hypotenuse
Since you have two sides
you dont need that
all that was asked for is the oppoosite
so the correct course of action from here is to acknowledge that we are DONE with this problem and to move on
Oh yeah!
Okay i sent my homework, im really sorry for stressing you out from that stupidity of mine lol @vale wigeon
and though im not kinda into math but im slightly reading algebra book i only know the polynomial methods LOLa
are you allowed to use the fact that $t + t^{-1} \geq 2$ for positive $t$?
Ann
because i have a feeling it'd be much much easier to do (d) using that than using part c

