#help-0

1 messages · Page 619 of 1

grizzled hull
#

wait do u think im only trying to find the tan value?

woeful pulsar
#

it looks like you are trying to find everything

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like sin cos cosec sec tan cot

grizzled hull
#

ye

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im confused on how to find it

woeful pulsar
summer gust
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"Registrants at a large convention are offered 6 sightseeing tours on each of 3 days. In how many ways can a person arrange to go on a sightseeing tour planned by this convention?"

Is this just 18, or am I looking at this wrong.

woeful pulsar
#

6 ways for first day 6 for second so 36 for first two

summer gust
#

why do you multiply them and not add them? also, it's 3 days, not 2

woeful pulsar
#

It should be easy to extend to 3

summer gust
#

yea, mb, didnt see you said for first two lol

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but why is it multiplied and not added

woeful pulsar
#

Because after each day one tour you can pick any day 2 tour

summer gust
#

hmm

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i guess i was under the assumption theyd only go on one tour

lime stirrup
#

how do you usually determine when to use vertical or horizontal strips?

woeful pulsar
lime stirrup
woeful pulsar
#

If you mean integrals, depends which one is easier

lime stirrup
woeful pulsar
#

Try both

calm kiln
#

This free?

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Is the answer correct

glossy nymph
#

Substitute π/6 in place of x

calm kiln
glossy nymph
#

You have to put π/6 instead of x in f(x)

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Then calculate the value

calm kiln
#

dont I just multiply sec2x and pi/6

glossy nymph
#

No that's not how it works

drowsy garden
#

a test has 10 multiple choice questions each with four possible choices and only one right answer a student decides to use a spinner with 4 equivalent sectors on it to randomly choose which answer to pick for each question. what is the likelihood the student gets no more than 2 correct

calm kiln
#

wtf

glossy nymph
#

You were given f(x)

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You have to find f(π/6)

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So replace x by π/6 and find value

glossy nymph
calm kiln
#

so that?

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without the x

glossy nymph
#

Nu nu

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X was inside sec right, 2x was an input for sec ()

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So put it there, not outside

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In functions, you give an input (x) and recieve an output [f(x)]. X is a placeholder variable and you substitute that for whatever value you want to put in the function

candid wedge
#

f(x) = sec(2x)
So f(π/6) = sec(2π/6)

calm kiln
#

I still dont get it

candid wedge
#

f(a) would be sec(2*a)

indigo jetty
#

$sec 2x$ is $sec (2x)$, not $(sec 2)x$

candid wedge
#

f(y) would be sec(2*y)

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That way

ocean sealBOT
calm kiln
#

oh I see

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I dont put the 2 outside

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I put it inside

candid wedge
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Yes

calm kiln
#

ok ty

candid wedge
#

It's sec(2x) like ken said

calm kiln
#

so the answer is sec(2pi/6)

indigo jetty
#

the 6 is in the brackets

calm kiln
indigo jetty
#

simplify the fraction

calm kiln
#

2?

indigo jetty
#

how do you simplify $\frac{2}{6}$?

ocean sealBOT
calm kiln
#

its 2pi

ionic jewel
#

how the heck do you simplify 2/6 to 2pi

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oh

calm kiln
#

I got 2

calm kiln
indigo jetty
#

so in other words, you're writing the exact value of sec(2pi/6)?

ionic jewel
#

thats right but i feel like you just plugged it into a calculator

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well i guess you didnt need to simplify in that case anyways lmao

indigo jetty
#

You have to be concise when answering our questions, not just put some random number

calm kiln
#

wdym

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I just plugged it into a cal

ionic jewel
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is that what they want?

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i guess it is

calm kiln
#

yea

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Is this correct?

ionic jewel
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,w tan(39 degrees) = x/72

calm kiln
#

thanks

flint holly
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Can anyone show me how to do this

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<@&286206848099549185>

ionic jewel
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$x^{-n} = \frac{1}{x^n}$

ocean sealBOT
ionic jewel
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switch both negative exponents to this form (to make them positive) then reduce from there

flint holly
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how do I switch it to positive?

ionic jewel
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the formula i just wrote

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alternatively you can just think of it as "flipping" it over the division sign

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so in yours you can just flip the fraction and make them both positive

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y^2/x^5

flint holly
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oh ok thats pretty simple

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is it the same for this equations?

ionic jewel
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distribute the ^2 to everything in the fraction then flip the negative exponent terms

flint holly
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oh ok I'll try that one sec

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I got 16y^-4/x^9

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I know its wrong

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how do I get rid of the 16

ionic jewel
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okay let me go through the whole problem

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@flint holly what exponent is the x to?

flint holly
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-3

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sorry its blurry

ionic jewel
#

Original problem:
$${(\frac{x^{-3}}{4y^{-2}})}^2$$
Distribute the squared
$$\frac{x^{-6}}{16y^{-4}}$$
"Flip" the negative exponents
$$\frac{y^4}{16x^6}$$
ta-da

ocean sealBOT
flint holly
#

oh ok

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so you don't bring the 16 up with y

ionic jewel
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the 16 does not have a negative exponent

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the only reason it goes up is to get rid of the negative in the exponent

flint holly
#

ohhhhh ok that makes sense

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thanks

alpine sable
#

Hello, I need a bit of help with Linear Algebra. I need help with Wronskian.

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I am trying to solve W(cosh(7x),sinh(7x))

alpine sable
#

hello

alpine sable
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Lost xOx

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<@&286206848099549185>

shrewd sable
# alpine sable

When you do the first line of the determinant, why did you do 7xcos(h) rather than cosh(7x)?

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Also how do your derivatives suddenly have an h variable?

alpine sable
#

Hi help me please

gray isle
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is the ^g supposed to indicate gradians?

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and what's the desired unit of the final answe?

alpine sable
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Whats 2 + 1

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Hmmm...

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I'm still lost

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I just put my derivatives in that order because it looks less confusing to me

alpine sable
gray isle
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that references degrees °, minutes ', seconds "

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which g is not used for

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(unless you replied to the wrong thing and didn't tell me or confirm what g is supposed to be)

thin surge
#

No

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You know it if the question gives it to you

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Or you find it by finding range

gray isle
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parentheses/brackets (in context) can be used to represent an interval

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here [-4,1] represents the interval between +4 and 1 including both -4 and 1

alpine sable
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How do i solve this

thin surge
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So here you cannot put 7 like x can not be equal to 7

thin surge
#

Which is perpendicular/hypotenuse

magic lichen
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@misty pebble it’s not asking for endpoints. It is stating the entire interval of inputs for which the function is defined (the functions domain). In the second case, it includes everything between 0 and 7, but not 7 itself

alpine sable
#

What do i do after sine 52

thin surge
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Then calculate hypotenuse from it which will give you X

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@alpine sable

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Yesss

alpine sable
thin surge
alpine sable
#

Okay let me solve it and tell you x

thin surge
#

Okay

alpine sable
#

Is it 5.12 cm?

thin surge
#

Noo

alpine sable
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How do i do it then

thin surge
#

Sine52 is 0.788

alpine sable
#

Yes

thin surge
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So you calculate.6.5/0.788

alpine sable
#

Oh ok

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8.24?

alpine sable
thin surge
magic lichen
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Open dot corresponds to )

alpine sable
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Does anyone know the rule for bearings how to solve them

magic lichen
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Closed dot to ]. It’s just a graphical notation and a textual notation of the same concept. Any function maps some set of numbers to another set of numbers. The input set is called domain and the output set is called range. The combination of the function itself and the domain it is defined on will generate the range

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Functions are just tools we define and use and we are allowed to tell the function what numbers it is allowed to exist on (domain) sometimes we want to represent every number in an interval but might not want to include the endpoint(s) of the interval in the allowed inputs

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There are bounds but not necessarily strict endpoints. Since you can fit an infinitude of numbers between 6.999999999999 and 7, it would be impossible to write that as a closed interval with [0, 6.999999999999999]. The decimal would go forever

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Yes, [] means endpoints are in the domain. You still need to evaluate the function at those inputs to obtain the corresponding values in the range though

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They are considered endpoints. The important thing is that anything in the domain can be evaluated by the function. For the solution of the second one, notice that the range includes f(7) = 28 as an open boundary. That’s because 7 isn’t in the domain so 28 isn’t in the range, but it is a bound in the range such that f(6.999999999999) approaches 28

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When really the last value in the range is 27.9999999999999

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Make sense?

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I can’t specify exactly the highest value in the range because I would have to keep typing 9 after the decimal. Mathematicians are lazy so this is the easier way to write it while meaning the same thing

alpine sable
#

How do i solve this?

misty pebble
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I think I was going wrong by looking at the first one, which had both endpoints at 0 on the y

magic lichen
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Except one will have a closed dot and the other an open dot

misty pebble
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So I assumed that was the difference

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Thank you for the help

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I seriously appreciate it

magic lichen
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Sure!

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For the first one, the endpoints of the domain don’t produce the endpoints of the range. Instead you just take the lowest and highest value produced by the function when evaluated for all points in the domain. Same is true for the second one but those happen to correspond to then endpoints of the domain

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I assume it’s asking the same thing. From the picture alone it’s not asking anything but I assume the textbook or assignment is just lazy

misty pebble
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I mean is that the same info? Like just giving you the function and then the domain that it works in

magic lichen
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Yup

misty pebble
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They both ask for intercepts and turning point, I should have included that

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Well thank you

magic lichen
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Just different notation for the same thing

misty pebble
#

I can stress how thankful I am

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can't

magic lichen
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No worries

alpine sable
#

Hi guys

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Can someone help me with my homework

bold token
#

show it

alpine sable
bold token
#

isnt that volume?

alpine sable
#

Yeah volume of a cone

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But I don’t know how to do it

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But what’s the answer

bold token
#

jsut plug in the givens

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divide 2 the diameter, to get the radius

alpine sable
#

I don’t know how to do that

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I’m stupid

bold token
#

15.6/

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2

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you get the radius

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now you complete the values h, and r

alpine sable
#

Bruh I’m stupid

bold token
#

then you plug it on the formula

alpine sable
#

Ima just ask someone for answers

bold token
#

radius is half the diameter

alpine sable
#

This server is so fucking ass

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I just need the answers

bold token
#

what

runic citrus
#

im just tryning for fun

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could someone help?

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<@&286206848099549185>

bold token
runic citrus
#

hey man

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can u help?

bold token
#

I don't understand that

runic citrus
#

oh ok nvm

ionic jewel
# runic citrus

don't have paper near me but does turning it all into sin and cos then combining help at all?

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might end up with some double/half angle identity or whatnot and be able to go from there

runic citrus
#

i did get that idea

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do i turn cot2 into cos/sin?

acoustic shadow
ionic jewel
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so cos^2/sin^2

runic citrus
#

cos2/sin2 then

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yep

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cosec to 1/sin?

ionic jewel
#

cot = cotangent = 1/tan

ionic jewel
acoustic shadow
runic citrus
#

3(1/tan^2x) - 14(1/sinx) - 2 = 0

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dont know what to do next

acoustic shadow
#

Why are you converting it to sin and cos

ionic jewel
#

that often helps

runic citrus
#

do i do it to 1/tan then?

acoustic shadow
#

It’ll create a mess

acoustic shadow
ionic jewel
acoustic shadow
#

Well do you know the basic 3 trig identities

runic citrus
acoustic shadow
#

Write them

runic citrus
#

sin , cos , tan?

alpine sable
#

Can anyone show me step by step how to do this

runic citrus
#

could u pls wait?

ionic jewel
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good spotting ^

runic citrus
#

do i multiply 3 with 1/tan^2x?/

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?

ionic jewel
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no

acoustic shadow
runic citrus
#

umm

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oh ok

acoustic shadow
#

Sin^2 + cos^2 =1 those

runic citrus
#

ah that

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ok yeah

acoustic shadow
#

Write the one with cot

runic citrus
#

cot^2 + 1 = cosec^2

acoustic shadow
#

Can you replace cot^2 in your original q

acoustic shadow
runic citrus
#

dont i need +1 for that

acoustic shadow
#

And then assume cosec as t and it’ll be a quadratic in t

runic citrus
#

oh wait

acoustic shadow
runic citrus
#

cosec^2 - cot^2 = 1?

acoustic shadow
#

No cot^2=cosec^2-1

runic citrus
#

oh ok

acoustic shadow
#

Now solve it own your own

runic citrus
#

3(cosec^2 x -1) - 14 cosec x- 2 = 0

acoustic shadow
#

Yep

runic citrus
#

thank u so much

alpine sable
#

@acoustic shadow

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Can you help me now?

acoustic shadow
#

Write the prime factors of 600

acoustic shadow
alpine sable
#

No

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Can you solve it step by step so i can understand

acoustic shadow
magic lichen
#

Factors are numbers that multiply with each other to equal another number (the product). Prime factors are factors that are also prime numbers. Prime numbers are numbers whose only factors are 1 and itself

quaint trout
#

@alpine sable can you list the first few prime numbers so we can see if you know what they are?

acoustic shadow
magic lichen
#

Imagine a big tree with a single number at the top (600) and two branches coming out with two factors, say 200 and 3, then go to each of those and keep expanding the tree down until you are left with only primes

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Definition is the only way to know what is being asked

alpine sable
#

Oh okay now i get it one i solve it can you see if its right

magic lichen
#

Then by multiplying all of the primes together you will get 600

subtle nimbus
#

I need help with this question ⁉️
Write du incase of u(x) and in case of u(x,y,z)

subtle nimbus
#

Yes

ionic jewel
#

in that case i have no idea what it's asking sorry

magic lichen
#

There’s some context missing here

spice cape
#

a student takes a test and she attempts 2 questions (multiple choice) each question has 4 options, what is the probability of her getting:2 correct and 0 correct?

alpine sable
#

Is this wrong?

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Isnt it x is minus 4cor x is minus 2

ionic jewel
#

1/4 chance each

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(1/4)(1/4) = 1/16

alpine sable
spice cape
misty pebble
#

A roller coaster is modeled by the function f(x)= 0.001(x-10)(+20)(x-40) What is the height above ground level of the track at x = 50?

ionic jewel
misty pebble
#

I'm using a graphing calculator to plot this and when I do y cal and enter x=50 it says its not in the domain

ionic jewel
spice cape
ionic jewel
#

yes

spice cape
#

ok what about 0 correct?

ionic jewel
misty pebble
#

Yes apologies.

ionic jewel
#

there you go, calc should get it now

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i have no idea I'm bad at stats, go to another channel and repost question minti

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3/4 chance of getting it wrong the first time

spice cape
#

ok all good

ionic jewel
#

3/4 second time

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9/16

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probably (tm)

spice cape
#

alright cheers

misty pebble
#

It still gives me the domain error

ionic jewel
misty pebble
#

f(x)= 0.001(x-10)(+20)(x-40)

ionic jewel
#

,w f(x)= 0.001(x-10)(x+20)(x-40) where x = 50

ionic jewel
#

there you go

chrome spade
#

How do I do this questino?

ionic jewel
#

i feel like this is something you have to look up on a table, how many SD above the mean the 80%ile gets you

chrome spade
#

it didnt provide a table tho

magic lichen
chrome spade
#

I tried the Z-score formula

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i got 167.2cm instead of 167.83

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0.8 = (X-156)/14

magic lichen
#

Z-score tells how many standard deviations above/below the mean. Multiply z-score by standard deviation and add to mean

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You need the z-score for 0.8, not 0.8 itself in the formula

chrome spade
#

how do I do that lol

magic lichen
#

Otherwise it looks okay. Google z-score of 8th percentile. It’s defined by a formula and is usually precomputed in a table in most statistics textbooks

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Check the link I posted for explanation about how it’s used.

chrome spade
#

ok thankyou

magic lichen
#

Coincidentally the z-score for 80th percentile is quite close to 0.8 which is why your answer was close but not exact

severe venture
#

I really don't understand the question that much

spark prawn
#

@severe venture Do you still need help?

severe venture
#

Yea

spark prawn
#

So how much of the question do you understand?

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Are there specific words that are confusing you?

severe venture
#

I really cant explain I do all my questions in my head

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I just cant understand what they mean with consecutive integers and middle integer

spark prawn
#

Consecutive means immediately after

ionic jewel
#

consecutive integers are in a row

spark prawn
#

So 1, 2, and 3 are consecutive integers in a row

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Ye

severe venture
#

Ooh okay

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I think my answer is correct

spark prawn
#

The one you've highlighted?

severe venture
#

I submitted O_O

spark prawn
#

That's not the correct answer

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Ah

severe venture
#

I wanna die

#

yay

tawny lion
unborn merlin
#

any calculus experts here

#

having a tough time with a calculus qn

wicked ember
unborn merlin
#

can someone pls solve this

cyan anvil
#

1-2x^2+x^4 =0 x=?

unborn merlin
cyan anvil
unborn merlin
#

+or -1?

#

thats not possible

stark lantern
#

$(x^2 - 1)^2 = x^4 - 2x^2 + 1$

ocean sealBOT
#

error 404

stark lantern
#

you should be able to obtain the solutions from this

spark prawn
#

I'm not sure how to solve this (after I've made equations for probability in relation to other points)

woeful pulsar
#

answer is 0, because once you reach b the walk ends

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and you don't get the chance to move to c

hardy geyser
#

3x + 4y = 7xy yes?

woeful pulsar
#

but probably no

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substitute x=1 y=10 to see it be obviously false

spark prawn
#

p(c) = 0
p(b) = 1

woeful pulsar
#

wait

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what

spark prawn
#

Hm?

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The starting vertex is a from which I need to figure out the probability of reaching vertex b before c

hardy geyser
#

X^3 times Z^4 can’t be multiplied because they powers are different?

placid zinc
#

You can multiply them. Their product is x³z⁴

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That doesn't simplify, because x and z aren't the same thing

hardy geyser
#

Xz^7

placid zinc
#

So it depends on the base

hardy geyser
#

XZ^7

placid zinc
#

x³z⁴ ≠ xz⁷

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xxxzzzz ≠ xzzzzzzz

hardy geyser
#

yeah that’s what I meant thank you

plush wagon
#

Can you tell me why is 7<X<11

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I mean X should be less than both 11 and 7 right?

placid zinc
#

,w graph (x - 11)(x - 7)

placid zinc
#

You care about where that quadratic is below the x-axis

plush wagon
#

Oh I got it thank you

cosmic agate
#

where is the maximum and minimum for this function?

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is the maximum 0, 0 or 15?

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this is calc 1 btw

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high school stuff

vale wigeon
#

(0,0) is a local maximum point, and (15, 0.938) seems to be a local minimum point

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this function has no global maximum due to the presence of VAs near which it explodes to +∞ at least once

cosmic agate
#

how is it a maximum

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when its lower than the second point?

vale wigeon
#

i said local maximum for a reason.

cosmic agate
#

local?

vale wigeon
#

relative maximum, if you're more accustomed to that terminology.

cosmic agate
#

local to that specific interval?

vale wigeon
#

also are you not able to send an actual screenshot instead of this crude photo?

spark prawn
#

Windows key + print screen is for screenshots on Windows

vale wigeon
#

x=0 is a maximum point if you consider your function on the interval [-1, 1] for example

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you can just press printscreen and it'll copy the screenshot into your clipboard

cosmic agate
#

wait so like when it says local maximum

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it means like the maximum point at that speicifc part

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because the actual maximum is infinite

vale wigeon
#

cut that last part

cosmic agate
#

oh theres no maximum

vale wigeon
#

no, what's wrong is your implication that for local maxima to exist the global maximum must be infinity

cosmic agate
#

because like - x^2

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then the maximum could be like 0,0

vale wigeon
#

the 2nd and 4th points highlighted on this graph are local maxima, even though the global maximum exists and is equal to about 6.1 and is achieved at x=0

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for the function i just showed

cosmic agate
#

RIGHT

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so a question could ask for either global or local maximum/>

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and in my function since there is no global maximum or minimum ij ust write the local max and min right

vale wigeon
#

i do not know what the exact wording of your question was so i cannot tell you what you are supposed to write

cosmic agate
#

it just says

find maxmium and minimum

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points

vale wigeon
#

"find maxmium and minimum
points"
is that the question verbatim?

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no alterations, nothing omitted?

cosmic agate
#

yes

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thats

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it

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i swear to god

cosmic agate
#

and the numerator is undefined

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what do i do?

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solve f(x) = 0 for the denominator?

vale wigeon
#

??

cosmic agate
#

if i have this

vale wigeon
#

give me a moment.

cosmic agate
#

x^ = -(32/24)

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that is undefined for the numerator

alpine sable
vale wigeon
#

you did not find the second derivative properly.

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you did not find the second derivative properly.

vale wigeon
#

you have f'(x) = -8x/(x^2 - 4)^2, yes?

cosmic agate
#

yes

vale wigeon
#

wait, ok, let me double-check

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,w d/dx (-8x/(x^2-4)^2)

vale wigeon
#

okay, so my point about you messing up the derivative stands, even if you did not mess it up as much as i thought you had

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anyway, your second derivative simply does not have any zeros.

cosmic agate
#

how did i mess it up

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no

cosmic agate
#

8

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not 8x

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its 8/(x^2 -4) ^ 2

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not 8x

vale wigeon
#

oh wait you have a minus sign there

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then you did not mess up

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you did not show your process at all however

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so like, maybe do something about that

cosmic agate
#

i dont care if i lose a mark about that

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its such a pain in the ass

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ijust need to hand it in

vale wigeon
#

anyway, whatever

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f''(x) = 0 has no solutions

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you have no inflection points

cosmic agate
#

...

#

oh

cosmic agate
#

wait but here

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at 0,0 is a turning point

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at a turning point isnt the derivative equal to 0

vale wigeon
#

but we are not talking about the first derivative

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we are talking about the second derivative

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and we are not talking about turning points

cosmic agate
#

why do we have to find the second derivative instead of the first?

vale wigeon
#

we are talking about inflection points

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...

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who said you "have to" do anything

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you wanted to analyze this function for concavity, did you not?

cosmic agate
cosmic agate
peak niche
#

Can someone help with a question from a test i just did? Everyone got a different answer and i want to know what the right answer is

vale wigeon
#

you don't need to reply-ping me at every single message

#

@peak niche channel busy please move

cosmic agate
#

sorry

peak niche
#

Where should i go

cosmic agate
#

right points of inflection are diferent from max and min points right

alpine sable
#

Come to chanel 4 @peak niche

vale wigeon
#

one of the other 9 questions channels that does not have a convo going on in it right now @peak niche

vale wigeon
#

sometimes a point may be both

cosmic agate
#

what are points of infelction

#

...

#

haha

vale wigeon
#

they are the points where your graph goes from concave up to concave down or vice versa

#

but anyway you need the second derivative in order to find these

#

since f''(x) = 0 is a necessary condition for being an inflection point

cosmic agate
# cosmic agate

right and i got the second derivative and on this graph there is no graph from concave up to down right

#

it just goes up or down

#

because of the vertical asymptope

vale wigeon
#

no

#

your graph is concave up on (-∞, -2) and on (2, +∞), and it is concave down on (-2, 2)

#

as can be seen from the signs of f''(x) on those intervals

cosmic agate
#

right

#

but there is no point where it transitions from concave up to concave down right

vale wigeon
#

yes, there are no inflection points

#

as it happens, both concavity changes occur across a vertical asymptote in your case.

cosmic agate
#

right

#

thanx for helping me

#

I know I ask alot of basic shit

#

but i work like 60 hours a week and i dont have alot of time to study

vale wigeon
#

sheesh

#

wait how old even are you

cosmic agate
#

20

vale wigeon
#

oh

#

i was wondering why you would have a job that takes 60 hours a week

cosmic agate
#

i work 3 part time jobs to make sure i have enough money to move out

#

i am apply to a school that is across the country

#

and i need to send some money to my parents too

vale wigeon
#

christ

cosmic agate
#

yeah

#

if i stay in my hometown i will hang myself or something

#

everyone else does like heroin or works in a steel mill

#

and all the girls sell mlm shit

#

just existing here makes me want to die a college acceptance is a golden ticket to freedom

#

sorry to ask, what is the difference between the intervals of increasing and decreasing

#

and intervals of concavity

#

are they the same thing?

vale wigeon
#

no, they are not the same thing.

#

in fact a function can have any combination of increase/decrease and concave up/concave down on a given interval

#

concavity is about the placement of your function's graph relative to chords connecting points on it

cosmic agate
#

my friend said that they are the same thing and he used the same logic to find intervals of increasing and decreasing to interals of concavity

#

but since concavity uses 2nd derivative

#

he is wrong af right

vale wigeon
#

your friend is right only about the mechanical part

#

for most functions, yes, concavity is directly controlled by the sign of the second derivative

#

but conceptually it is a different thing altogether

#

it would be good if you and your friend tried not to fall into the plug-and-chug mindset that makes people into meat-wrapped calculators in math class

celest void
#

Hmm is this channel vacant?

vale wigeon
#

probably not

celest void
#

Aw

vale wigeon
#

unless joe bidome has no more follow-ups

cosmic agate
#

for now lmao

celest void
#

Yay which means It's vacant ig

vale wigeon
#

okay post your question here then

celest void
#

Hmm could someone help me with this theorem which goes something like "if a vector set is linearly independent, then its maximal and independent subset is the whole set itself'

#

I don't necessarily understand what this means

vale wigeon
#

its a bit of a tautological statement

#

if you have a set S of vectors and you know that S is linearly independent then every subset of S is linearly independent too

#

and thus among the linearly independent subsets of S there is only one that is maximal, ie not contained in any other: S itself

celest void
#

So maximal and independent subset is basically a set that's contained in itself?

#

I know how to compute by using the rank of vectors or something but i don't get what it actually is

quick surge
#

how do i do this
if this channel is busy please tell me

vale wigeon
#

maximal is a notion from order theory

#

but roughly: if you have a family of sets, a maximal set is a set which is not contained in any other set from the family.

quick surge
#

oh its busy sorry

celest void
vale wigeon
#

"independent subset" just indicates which family we're talking about maximality in

celest void
#

Wait if you don't mind can you elaborate more on that

#

I didn't quite get it 😐

#

I get the maximal definition from what you've mentioned prior though

celest void
#

Ty! ❤️

jaunty jasper
#

Can someone help with part D

#

What i have tried so far

#

Pls help

alpine sable
#

Please write tan as sin/ cos and cot as cos/sin and open the bracket

#

Ull get 2 sin^2+2 cos^2

humble merlin
#

yes it proofs itself after doing that

#

@jaunty jasper do you get it?

jaunty jasper
#

Yeah im just trying it out

#

Ty

cosmic agate
#

for the function the y intercept equals 0 right

why is it on the graph crossing it 3 times?

#

oh no im an idiot

#

thats the x intercept

viscid dawn
#

Is there a way i can get the formula of 10*11*12*13 .. up to *30 like 10! is 10*9*.. to *1*0?

tawdry jasper
#

Should be 30! / 9! I think

#

@viscid dawn

viscid dawn
#

Wow

#

Yeah

#

Thanks haha

#

Didn't remember of that

tawdry jasper
#

np

hushed topaz
#

I need help with question B

#

please

void yoke
#

Gradient probably here means slope. Find an expression with h and numbers that represents the slope between P and Q.

hushed topaz
#

how do I do that lol

#

@void yoke

void yoke
#

Given two points, find the slope. The points are given as P: (1, 2) and Q: (1 + h, f(1 + h)).

hushed topaz
#

so y2 - y1 / x2 - x1 ??

void yoke
#

watch the parentheses ...

#

(y2 - y1)/(x2 - x1)

hushed topaz
#

yeah

#

❤️

void yoke
#

so put it all together?

hushed topaz
#

(2/(1+h^2) - 2)

1 + h - 1

#

is that right

#

and then simplify from there

#

wait

#

but the squared for the numberator is on the outside of bracket so I messed up

void yoke
#

yep, good catch.

still crest
#

Is this busy?

hushed topaz
#

yes

still crest
#

Alright!

hushed topaz
#

im still writing lol

#

soz

still crest
#

No worries

hushed topaz
#

ok

#

so does it become

#

bruh

prime mist
#

ah shit is this bussy im sorry haha

hushed topaz
#

all g

#

2- 2(1+h)^2

(1+h)^2

h

#

@void yoke

void yoke
#

almost. Technically the lower fraction bar needs to be wider than the top one.

hushed topaz
#

yeah true

void yoke
#

anyway, that'd be fine for me but it's up to you to make sure your instructor's formats for answers are followed.

hushed topaz
#

wait

#

so then what does it simplify to?

#

@void yoke

void yoke
#

2 🙂

#

wait no

hushed topaz
#

bc that's the answer

void yoke
#

oh sure looks good to me.

fickle ridge
#

Hi guys

void yoke
#

from your last "text" answer you can finish dividing through by h (it then gets multiplied by the denominator)

fickle ridge
#

how can i solve this

#

?

void yoke
#

hey um, can you go to another room 🙂

#

we're still discussing a problem! 🙂

still crest
#

@void yoke if you're working with others I would appreciate to stick to them, ty

void yoke
#

2- 2(1+h)^2

h(1+h)^2

-2h^2 - 4h

h(1+h)^2

hushed topaz
#

wait

#

but that's diff to answer

#

when factorised

void yoke
#

@hushed topaz so then I think you got it?

#

just factor an h from the top and cancel

hushed topaz
#

oh true, yes ok thanks ❤️

wary stream
void yoke
#

yep no worries mozzy.

still crest
wary stream
#

If there's not many people answer, IE like 2 people helping and all the channels are going off, they can help multiple channels at once, if they know what they're doing

still crest
half steppe
#

hello. I am trying to understand how to do continued fraction expansion, specifically when computing the square root of a number n : https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Continued_fraction_expansion
I got it right for sqrt(2) and sqrt(3) but I fail at sqrt(7).
this is the correct answer: https://www.wolframalpha.com/input/?i=Convergents[sqrt(7)%2C10] for sqrt(7)
but when i do it myself i get

{2 , 11/4 , 34/11 , 101/34 , 304/101 , 911/304}```

Wolfram|Alpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels.

Methods of computing square roots are numerical analysis algorithms for finding the principal, or non-negative, square root (usually denoted √S, 2√S, or S1/2) of a real number. Arithmetically, it means given S, a procedure for finding a number which when multiplied by itself, yields S; algebraically, it means a procedure for finding the non-nega...

#

can someone help me understand my mistake?

fickle ridge
#

how can the last question be solved?

rose glade
#

yo some one know how to solve

alpine sable
#

O is the center right

rose glade
#

yes

#

arc length

alpine sable
#

This means arc AB is a + 50

#

So a + 50 + 3a + 10 = 360

#

4a = 300

#

a = 75

#

Plug a in

#

50 + 75 =125

rose glade
#

we always

#

need collect all a that we know

#

and make equation

#

then find yes?

#

how to find measure of central angle if we know radius and pie

urban matrix
#

i need help on this

analog terrace
#

quick question. how do you read P(S∩D)

alpine sable
#

P(SnD)

shell widget
#

probability that S and D both happen

#

or occur

peak niche
#

Quick question I'm gonna prepare for A level maths and further maths over the summer a little what topics should I study?

#

@urban matrix just add up the numbers my guy

#

Use the radius to find Diameter to find circumfrene which is pi D

#

And divide by 2 or 4 depending on if its half or quarter of a circle

autumn fjord
#

How do I do this

urban matrix
peak niche
#

Ok so the radius of turn 1 is 3 meters

#

So the diameter of the circle is 6 meters

#

Circumference is Pi x D which is 6 pi

#

So turn 1 is a quarter of a circle so that's 1.5 pi

#

Do that for each turn and add them together then add that to the straight lines

urban matrix
#

alright should i fill in 1.5 on the first side of it

peak niche
#

That's for turn 1

#

Turn 2,4 and 5 are a quarter too which makes a full circle so thats 6 pi

#

6, 8 and 9 make a full circle so thats another 6 pi

urban matrix
#

and should i write these on the drawing of the shape or in the first question

peak niche
#

Turn 3 and 7 have radius of 2.25 so diameter is 4.5 which means the full circumference is 4.5 pi

#

And 3 and 7 make a full circle so add 4.5 pi

#

So total 16.5 pi

#

Then add 20,30,8,6,6,12,30

alpine sable
#

are the triangles similar

#

Water volume: V=550 m3
Top surface area of water: As=171,000 sq mi
temperature: T∞=32-49 °C goes down to 10-22 °C in winter
Water temperature: Tw= 30 ∘C down to 8°C in winter
Relative humidity of water in room air: 15 %

Rain does not exceed 8 inches per year
How much years would it take for that water to dry up, happy_cry_cat please

urban matrix
#

alright thank you

#

if i have trouble again can i ask you for help or no

alpine sable
#

yes

autumn fjord
#

<@&286206848099549185>

alpine sable
#

bruh

peak niche
#

@alpine sable 180-90-63 is 27
180-124-27=29
No, one has an angle of 27° and the other is 29°

peak niche
#

Np

alpine sable
#

how to solve angle 1 , 2, and 3

#

no

#

angle 1 2 4 5 6 7

peak niche
#

Angle 1 is 180-76

#

Angle 7 is the same as 76

#

Angle 5 is the same as angle 1

alpine sable
#

6 is the same

#

as 76

peak niche
#

Angle 4 = angle 1

#

Angle 2 = 76

versed osprey
#

Example 6, how did we get 11 and 3 as the two radii

peak niche
#

Angle 6 is 76

#

Etc etc

alpine sable
#

and 8 is same as 1

peak niche
#

Yes

alpine sable
#

alright thanks

#

whats the value of x

peak niche
#

Sum of angles in polygon is sides-2 x 180 so 3x180= 270

#

270-250

urban matrix
#

alright these questions follow up the picture i sent earlier

peak niche
#

Wait

alpine sable
#

20

peak niche
#

My bad

real sinew
#

,calc 3x180

ocean sealBOT
#

The following error occured while calculating:
Error: Undefined symbol x180

peak niche
#

3x180 is 540

alpine sable
#

lol

peak niche
#

I did 3x90

#

540-250

#

Then divide by 4

alpine sable
#

72.5?

#

is the sum of x

peak niche
#

Yeah

#

@urban matrix 1609 divided by lap length

alpine sable
#

thanks

urban matrix
#

alright 1609 divided by 120

peak niche
#

Then 1609x50 and divide by lap length

#

And trunkate

#

(cut off decimal)

#

Since it says full laps

urban matrix
#

wait do i do 1609 divided by the lap length first or 1609 x 50 divided by lap length

peak niche
#

1609 / lap length is the first question

urban matrix
#

ohhhh alright

peak niche
#

1609 is a mile so 50 mile is 1609x50

#

Then divide by lap length to find how many laps

#

Cut off decimal for how many full laps

urban matrix
#

gotcha

#

for number 2 i got 13.4083333

#

should i round it

peak niche
#

13

#

It says how many full laps

#

0.4 laps isnt a full la

willow bluff
peak niche
#

Lap

willow bluff
#

Can anyone help me?🥺

peak niche
#

@willow bluff 42.72/80x360 is full area

peak niche
#

Area is pi x r^2

#

So divide by pi and square root right

urban matrix
#

and number 3 i got 670.416667 and since you said cut off the decimal would it just be 670

peak niche
#

Sorry i thought the other one was the second one

#

Round the other one to nearest 2dp or something

#

Make that one 670

#

@versed osprey I'll see if i can help u

#

I'm only 15 i came here for help myself but i seem to be capable of helping some people here

versed osprey
#

Yeah ok

#

Wait nvm

#

I got it, thanks a lot for responding tho

peak niche
#

Alright nice

willow bluff
#

@peak niche I got 192.24 for the area. How do I get radius?

real sinew
#

Area is pi*r^2

peak niche
#

Divide by pi

real sinew
#

So you can work that equation backwards and solve for r

peak niche
#

Then square root answer

#

Around 7.723

#

Oops

#

7.823

#

Mistyped

#

You can check by doing pi x 7.823^2 , divide that by 360 and x by 80 to see if you get 42.72

#

1/-1 is -1

#

Uh

#

Wait lemme wrap my head round this

#

So -1>x

#

Waif

#

Sorry

#

Wrong sign

#

Or is it

livid jolt
#

x>-1

peak niche
#

If you make the number bigger then it doesn't work

#

So -1<x

#

Because making x equal to or any bigger than -1 and it doesn't work

versed osprey
#

Guys “-r -r” is “-2r” right?

#

Thanks a lot man

peak niche
#

Yeah

versed osprey
#

Imma head out

livid jolt
#

for positive values of x
-1 < 1/x
multiply both sides with x
-x < 1
multiply both sides with -1
x > -1

and similarly

1/x < 1
1 < x
x > 1

taking intersection u get x > 1

peak niche
#

1/-0.5

#

Doesnt work

#

So x smaller than -1 or bigger than 1 right

urban matrix
peak niche
#

@urban matrix 15x8 for the inside rectangle excluding edges

#

Then do radius X 15 X 2 for top and bottom

#

Then radius X 8 X 2 for left and right

#

Then add pi X radius^2 for the four quadrants

#

Since the 4 quadrants make a full circle

#

Then basically add all the areas up

urban matrix
#

thanks

still crest
#

Is this busy?

peak niche
#

Nah

still crest
#

I'm having trouble with c

peak niche
#

Yeah sorry I haven't learnt that yet I'm learning it next year

still crest
#

No worries

peak niche
#

@still crest what's the topic called again? Might learn it before next year in the summer

still crest
#

Definite Integrals

#

This was the last exercise in final exams

peak niche
#

The last question in mine (1 year behind you i think) only 3 of us got the correct answer which i checked with a maths teacher although the tests haven't been handed back yet everyone else got it wrong

#

There were about 100 people taking the test and there were lots of varied answers

still crest
#

You got it right?

peak niche
#

Yea

still crest
#

Congrats!

peak niche
#

Thank god

#

It wasn't hard imo but my logical process is on point most of the time

still crest
#

Let me send the problem again so it doesn't get buried

#

I'm having trouble with c)

strong furnace
peak niche
#

I don't even know how you'd write sin^2019 on a calculator

strong furnace
#

(Sin(x-2))^2019

still crest
#

I got scared by the big numbers so little to say, I only made some thoughts that we could substitute the x-2 with something

strong furnace
#

They want you to use what you proved in b

#

Can you connect the integral with lhs of b

stark creek
peak niche
#

If in doubt, the answer is 3

#

Don't take that seriously

still crest
#

Let us work the problem

strong furnace
#

You see the result from part b ?

still crest
#

Yes

#

2ab

strong furnace
#

Now what is b in this case?

#

What is 2a?

still crest
#

4

strong furnace
#

What about b

still crest
#

I'm not sure

urban matrix
#

wait oscar was i supposed to add all the areas up for number 5

#

or was that for number 4

peak niche
#

Quick question I know this is above my level but what is the function where it says f(2a-x)

strong furnace
#

b would be f(x)+f(2a-x) right?

still crest
#

How do we get that?

strong furnace
#

This

still crest
strong furnace
still crest
#

I didn't mean you said it

#

I meant that the exercise tells us that f(x) + f(2a-x) = 2b

strong furnace
#

Lol

#

True true

#

My bad

still crest
#

I don't know how do we get f(x) + f(2a-x) = b

#

Oh okay

strong furnace
#

It is 2b

#

But you have to just get this 2b

still crest
#

I can't find a way to correlate b and c part

strong furnace
#

Ok let's do it one by one

#

2a=4 right?

still crest
#

Yes

strong furnace
#

Now 2a-x=4-x

still crest
#

Right

strong furnace
#

Now write down f(x)

#

And write down f(2a-x) = f(4-x)

still crest
#

I did

strong furnace
#

If you add them what will happen?

still crest
strong furnace
#

f(4-x) and f(x)

#

Add these

still crest
#

Oh wait

#

We had 2ab

#

So now it should be hmm

#

2b?

strong furnace
#

Ok my bad

#

I missed something that I had in my mind

#

I just didn't tell you lol

#

f(x) is the integrand in part c

#

(sin(x-2))^2019.(x-2)^2018+3=f(x)

still crest
#

and substitute 4-x in

strong furnace
#

Now write down f(4-x) for this

still crest
#

f(4-x) = sin^2019(2-x) * (2-x)^2018 +3

#

Some typos, it's fixed now

strong furnace
#

You see how the thing inside the bracket is coming out to be -(x-2)?

still crest
#

Yep

strong furnace
#

Can we use some properties to convert it into just (x-2)?

still crest
#

I know that it works with cos(-x)=cos(x)

#

Does it work with sin?

strong furnace
#

Does it?

still crest
#

I'm not sure

strong furnace
#

You know sin(a-b) right?

still crest
#

Yes

strong furnace
#

Treat sin(-x) as sin(0-x)

still crest
#

Is it -sin(x)?

strong furnace
#

Yes

still crest
#

sin(-x)=-sin(x)

#

Ohh

#

And it's +

#

Because we do the same to the other one

#

-(x-2)^2018

strong furnace
#

But does the negative come out?

#

Look at the power

still crest
#

Oh right

#

It's even

#

english problems

#

So we can just swap it

#

And it won't change

#

Right?

strong furnace
#

So you get -(that expression)+3 for f(4-x) now I think you can add them like part b says to get your result?

wise jewel
#

Can someone please tell me how the hell my teacher solved this??????

still crest
#

This is busy

wise jewel
#

?

still crest
#

ty

#

@strong furnace haven't done this in a while

#

So we have f(4-x) = -sin^2019(x-2) * (x-2)^2018 + 3

strong furnace
#

Lol

still crest
#

Right?

strong furnace
#

Yeah

#

And this if f(2a-x)

peak niche
#

Damn u two still on the same question...

still crest
#

I can add f(x) + f(4-x)?

strong furnace
#

Yeah

still crest
#

Let me try this

harsh bone
#

Yo

still crest
#

We get 6

strong furnace
#

For 2b

still crest
#

f(x) + f(4-x) = 6

strong furnace
#

And a was 2

still crest
#

That's 3

strong furnace
#

So the result is ?

still crest
#

3

strong furnace
#

The result was 2ab,

still crest
#

I meant b is 3

#

So that's 12

#

2ab

strong furnace
#

Yes

#

And that should be the value of your integral

still crest
#

Okay I got it

harsh bone
still crest
#

Thank you!

peak niche
#

@still crest bruh i said 3 at the start lol

still crest
#

That wasn't the answer though

peak niche
#

Oh i thought u were solving for the letters or something i have no clue what an integral is

strong furnace
still crest
#

Integral answer is 12

harsh bone
#

Help me pls

strong furnace
peak niche
#

Oh cause like 2a is 4 and b is 3

still crest
harsh bone
#

Pls

stiff quiver
#

Please stop spamming.

still crest
harsh bone
#

I’m no

still crest
#

Stop spamming

harsh bone
#

I never said

#

I’m not

peak niche
#

Straight outta year 7

still crest
#

You are

stiff quiver
#

I'm in year 7 😦

peak niche
#

I have 1 more week of tests then I can drop 6 subjects

harsh bone