#help-0

1 messages · Page 576 of 1

raw inlet
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if anyone could help on b)

ionic jewel
vale wigeon
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no. your root starts out as sqrt(n^2-i^2)

kindred shard
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Can some1 help pls

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with #2 pls

undone copper
cold mica
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any one know how to solve this integral with the given two suggested integrals - i tried u = 2r/a as a substitution but i don't think my solution is correct

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C is just some constant

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main problem is if i use u = 2r/a for the e^-u i don't know how to handle the 1/r term infront

daring rapids
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Someone please help

cold mica
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-_-

spring harbor
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@daring rapids move to some other channel

daring rapids
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Oh sorry

spring harbor
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@cold mica maybe you can rewrite u=2r/a to r that way you can just put it in 1/r and get rid of it

cold mica
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well solving that for r gives r = au/2 but 1/r then means the integral has 2/(au)

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which means i have 1/u e^-u (once i take out the constants)

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which is not quite right

spring harbor
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mm not sure I don’t have pen and paper on me right now, maybe you could partial integrate it though

cold mica
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thats beyond the level im at so i dont think thats going to be the solution

spring harbor
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Ok you can just rewrite your function if that’s the case

cold mica
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what do you mean

spring harbor
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e^(-2r/a) = ... * ...

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I’ll let you think about it first

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Keep in mind that the 2 and a are constants, so if you have e^constant you can move it out

cold mica
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well thats = e^(-r/a)*e^(-r/a)

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but not sure if thats what you meant

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r is not a constant don't forget

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thats the subject of the integral

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unless you mean factor out e^(2/a0)

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leaving just e^-r

spring harbor
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Yeah that was my initial plan but it doesn’t work nvm

cold mica
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tho im not seeing it still since i have one in the denominator and one in the numerator

spring harbor
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Wait

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Did you forget to change the dr part?

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since you get du = 2/a dr

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Or dr = 2/a du

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This is a constant you can move it out

cold mica
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no i didnt forget that

spring harbor
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Then where’s the problem

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What did you exactly get?

cold mica
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well it doesn't remove 1/u e^-u

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when i need u e^-u

normal spoke
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Given the density d of particles, what's the average distance between two particles?

spring harbor
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Channel taken

normal spoke
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ah

cold mica
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i might've solved it @spring harbor

spring harbor
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What did you do?

cold mica
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i think i calculated the integrand wrong

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i think it was meant to be e^-2/ra

spring harbor
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So the question was wrong?

cold mica
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possibly but not sure yet still checking it all

spring harbor
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Alright that’s possible then

cerulean glade
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ik this is a math server but can someone help me with history?

alpine sable
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ik this is a math server
ok starting off well
but
oh no
can someone help me with history
thonkzoom

alpine sable
lost geyser
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my assumption is that
part a the displacement = 10 meters
part b professor buske is 10 meters away from his mailbox

severe silo
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B= {multiple of 5 from 1 to 50}

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Is {0, 50} a proper subset of B?

ionic jewel
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negative

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then i get -2.5m for the second

gleaming granite
ionic jewel
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tell us what you have and we can say if it's right

severe silo
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I think it's false

lost geyser
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@ionic jewel how did you get 7.5 for part a

ionic jewel
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integral from 2 to 4

ionic jewel
severe silo
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My guess is that it's because B is from 1 to 50 not 0 to 50

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I'm still very confused with this topic so I'm not sure

ionic jewel
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that's right

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i assume you know why that matters, but exactly

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it would be true if it was 0 to 50

severe silo
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Thanks @ionic jewel

rancid fern
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so if i have 5000 of something andsell it for 6500$, for 250 of it i pay 75$ how much profit would i get

ionic jewel
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what

ocean sealBOT
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number 1 crip gangster

woeful pulsar
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can you phrase it more clearly?

lost geyser
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they're paying 75 dollars for 250 units of something and they sold 5000 units of this soemthing for 6500 dollars

ionic jewel
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or post the original problem

lost geyser
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is what it sounds like

rancid fern
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exactly

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how much profit would i get

woeful pulsar
ionic jewel
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you don't have 5000 units of it how did you sell that much?

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as written it's 6500-75 with magic units appearing somewhere

woeful pulsar
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So your cost price for 250 units is $75 and your sales price for 5000 units is $6500... and you want the profit for selling 5000 units?

vale wigeon
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nobody ever has any clearer wordings

woeful pulsar
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ikr

lost geyser
ionic jewel
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i did integral from 0 to 4 lol

lost geyser
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would that even work... ?

ionic jewel
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why not

rancid fern
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so look i buy 250 apples for 75 dollars

ionic jewel
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you could make a lot of apple sauce with that

rancid fern
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and then i buy 5000 apples and sell them for 6500 how much profit would i get

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this is so confusing i know

alpine sable
ionic jewel
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you made it worse but i understand what you mean

woeful pulsar
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How much money does it take to buy 5000 apples?

ionic jewel
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so you need to buy 5000 apples at a price of $75/250apples

rancid fern
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yes

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exactly

ionic jewel
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how much to buy the apples?

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i love magic the gathering

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oh bye

stone scroll
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Can I ask for help

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It's physics but just the same, need to be computed lol

lost geyser
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how to find part b
delta x_k = 6 though right

woeful pulsar
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the first one is at?

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the picture divides it quite regularly

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but it's not very standard

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it's not a left sum or right sum

lost geyser
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first one is at x = 14 and then from there it adds 6

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but i dont know how to develop a formula for it

woeful pulsar
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when k=1, we want 14

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continue...?

lost geyser
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k = 2 we want 20

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i cant find a working formula where
10 + x = 14
10 + 2(x) = 20
10 + 3(x) = 26

woeful pulsar
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try starting with something other than 10?

lost geyser
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oh can we do that

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okay so 8 + 6k

stiff valve
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A product in a shop is reduced in price by 20%. At this reduced price the shopkeeper makes only 4% profit. What percentage profit (to the nearest whole percent) does the shopkeeper make at its normal selling price?
How do i form an equation for this?

woeful pulsar
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but you can say the cost price is c

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and see what happens

oak chasm
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@alpine sable OK, what two sides do you have, relative to the known angle?

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You have the opposite and hypotenuse.

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You correctly picked sine.

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So, write the equation.

ocean sealBOT
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Chai T. Rex

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Chai T. Rex

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Chai T. Rex

oak chasm
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No.

ocean sealBOT
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Chai T. Rex

oak chasm
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What do you get as the new equation?

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No.

ocean sealBOT
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Chai T. Rex

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Chai T. Rex

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Chai T. Rex

oak chasm
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Right.

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What is that?

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OK, now simplify.

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Right.

ocean sealBOT
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Chai T. Rex

oak chasm
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What's the left side?

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Of the equation.

hollow atlas
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bro

oak chasm
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No, that's the right.

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What's the other side?

ocean sealBOT
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Chai T. Rex

oak chasm
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That's the equation we started with.

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What's the left side?

ocean sealBOT
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Chai T. Rex

hollow atlas
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correct

ocean sealBOT
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Chai T. Rex

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Chai T. Rex

steel scaffold
ocean sealBOT
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Chai T. Rex

oak chasm
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Right, so what's the left side after you do that?

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What's the right side?

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No, without doing the calculation.

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What does the right side turn into?

ocean sealBOT
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Chai T. Rex

oak chasm
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What's the right side divided by it?

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No, that's not it.

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What's the right side?

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No, that's after you try to change it.

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What did it start as?

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Right, and then what did it become?

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Right, so let's go from there.

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Right.

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Divide by means you put what you're dividing by on the bottom.

ocean sealBOT
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Chai T. Rex

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Chai T. Rex

oak chasm
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Yeah, you were.

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OK, so use your calculator now.

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Yes, that's right.

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So, that's x.

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What's the next digit after that?

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OK, so the next digit is 9, which is 5 or higher, so you go up one.

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61.82.

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You're right.

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You're welcome.

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It means arctangent.

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Arctangent undoes tangent.

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So, which sides do you have relative to the angle they're looking for?

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No, probably not.

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OK, so let's do the equation.

ocean sealBOT
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Chai T. Rex

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Chai T. Rex

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Chai T. Rex

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Chai T. Rex

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Chai T. Rex

$\tan^{-1}(\tan(x^{\circ})) = \tan^{-1}(\frac{23}{31})$
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Chai T. Rex

oak chasm
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OK, so we simplify the left and get:

ocean sealBOT
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Chai T. Rex

oak chasm
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No, look at your answers.

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No, don't put it in your calculator.

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Look at your four choices.

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One of them matches our last equation.

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Right.

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Well, write down the equations.

ocean sealBOT
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Chai T. Rex

oak chasm
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No, that's the first answer.

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Cosine is CAH, right?

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What's the adjacent side length?

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What's the hypotenuse?

ocean sealBOT
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Chai T. Rex

oak chasm
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The first answer doesn't match what it should be.

ocean sealBOT
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Chai T. Rex

oak chasm
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The correct equation, I mean.

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That's the answer.

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I'm asking you for the correct equation.

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Sine is SOH, right?

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What's the opposite of B?

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No, the opposite side length.

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Which side is 25?

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Right, so it's not the opposite side.

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What's the opposite side length?

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What does adjacent mean?

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No, what does adjacent mean?

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Right, the leg next to the angle.

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What does opposite mean?

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Right, the leg across from the angle.

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What does hypotenuse mean?

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Right, or the side across from the right angle.

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No, it's not always diagonal.

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But it's always the side across from the right angle.

ocean sealBOT
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Chai T. Rex

oak chasm
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Which of SOH CAH TOA is for sine?

ocean sealBOT
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Chai T. Rex

oak chasm
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OK, what's the opposite side from B?

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What does opposite mean?

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What side is across from angle B?

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That's next to B.

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Right.

ocean sealBOT
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Chai T. Rex

oak chasm
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What's SOH stand for?

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What's the opposite side from angle B?

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What are the two sides next to B?

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OK, so write the triangle on paper with the letters and the numbers and the right angle symbol.

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Let me know when you've done it.

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Have you drawn the triangle on paper?

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OK, look at the triangle on your screen.

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We're going to find opposites.

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First, we'll find the opposite of angle A.

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What sides are next to angle A?

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Cover those sides up with your fingers.

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What side is still showing?

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Right, so that's the opposite side of angle A.

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Let's find the opposite side of angle B.

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What are the two sides next to angle B?

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OK, cover those sides up with your fingers.

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What's the side you can still see?

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Right.

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Let's do the opposite of angle C.

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What are the two sides next to C?

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Right, cover those up. What's left?

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Right. That's how you find the opposite side of an angle.

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OK, so what's the opposite of angle B?

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Right, what's the hypotenuse?

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OK, look at the right angle.

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What's the opposite side of the right angle?

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OK, how do we find the opposite side with fingers?

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No, cover up the sides next to the angle.

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What sides are next to the right angle?

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Where's the right angle symbol?

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Right, so C.

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What side is opposite the right angle?

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Right, so that's the hypotenuse.

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So, let's do $\sin(B)$

ocean sealBOT
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Chai T. Rex

oak chasm
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SOH CAH or TOA?

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OK, so what's the opposite side of B?

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What's the hypotenuse?

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OK, which angle is the right angle?

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Which angle has the right angle symbol next to it?

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OK, which angle is the right angle?

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OK, what sides are next to C?

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OK, cover them up. What's left?

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Right, so what's the hypotenuse?

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Right.

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So, what's the opposite side of B?

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What's the hypotenuse?

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No.

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What angle is the right angle?

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What side is opposite angle C?

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What's the hypotenuse?

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So, what's the opposite side of B?

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What's the hypotenuse?

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What's opposite over hypotenuse?

ocean sealBOT
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Chai T. Rex

oak chasm
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Does that match the answer?

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OK, so that answer is wrong.

ocean sealBOT
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Chai T. Rex

oak chasm
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Is that SOH CAH or TOA?

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OK, now there's a trick.

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C is the right angle, right?

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How many degrees is a right angle?

ocean sealBOT
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Chai T. Rex

oak chasm
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Right.

ocean sealBOT
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Chai T. Rex

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Chai T. Rex

oak chasm
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Is B the right angle?

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OK, so we can't just use our calculator.

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Is cosine SOH CAH or TOA?

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What side is adjacent to B?

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What's the hypotenuse?

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What letter is the right angle?

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What side is opposite from the right angle?

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That's the hypotenuse.

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Now, if 25 is the hypotenuse, it can't be the adjacent side, since that's a leg.

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So, what's the adjacent leg to B?

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What sides are next to B?

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Cover up the hypotenuse.

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OK, cover up the opposite and hypotenuse.

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Actually, let's do it this way.

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Let's find adjacent sides.

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Angle A. What sides are next to angle A?

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Which one is shorter?

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That's the adjacent side.

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Angle B. What sides are next to angle B?

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Which side is shorter?

vestal hollow
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How do I compute this limit? Isn't it infinity?? But according to calculators it's -pi/40...

limit as x -> -inf of (1/20)arctan(5x/4)

oak chasm
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@vestal hollow Well, you can move the constant out.

vestal hollow
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Yes, so lim x->-inf arctan(5x/4) should be -pi/2, which Google confirms. But I don't get how :( something about turning arctan into tan and then into sinx/cosx?

ocean sealBOT
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Chai T. Rex

$\lim_{x \to -\infty} \frac{1}{20} \arctan\left(\frac{5x}{4}\right)$
vestal hollow
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Yup!

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That exactly

ocean sealBOT
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Chai T. Rex

gray isle
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consider the range of arctan and how the tan function looks
and/or properties of tan and arctan in general

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and the limit should be clear

vestal hollow
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I see that it does approach a finite limit, but that's it :( how am I supposed to arrive at -pi/40 mathematically?

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I didn't realize it was -pi/40 from the graph

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But I did see that it went to a finite limit

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Just not how

ocean sealBOT
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Chai T. Rex

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Chai T. Rex

vestal hollow
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Undefined

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Oh

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approach

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xd

oak chasm
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Sure, but the limit.

vestal hollow
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Sorry

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Infinity

oak chasm
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Almost.

vestal hollow
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Oops again

oak chasm
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Tangent is the slope of the angle.

vestal hollow
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I'm sorry?

ocean sealBOT
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Chai T. Rex

oak chasm
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It becomes larger and larger negative values.

vestal hollow
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I don't understand, I'm sorry :(

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Wait

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I plotted

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Omg I'm sorry

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Doesn't the limit not exist?

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As we approach from the left, we get positive infinity

oak chasm
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Right.

vestal hollow
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From the right we get negative infinity

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Gotchya

oak chasm
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Hmm.

gray isle
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the range of arctan is (-pi/2 , pi/2)

vestal hollow
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Oh

oak chasm
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Ahh, yes.

vestal hollow
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So it should obviously approach -pi/2

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As we approach infinity

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negative

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brain is fried sorry, thank you both for being patient with me

oak chasm
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No problem.

vestal hollow
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Okay yeah I get it now, thanks

waxen pendant
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hey

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help me solve 29 please

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I broke up the (-3)^(n-1)

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which gave me

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-3^n * -3^-1

vale wigeon
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parentheses around the -3.

waxen pendant
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all over 4^n

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ohh shit whats going on ann

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I have another test how are u doing

vale wigeon
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this is a geometric series. do you know how to calculate the sum of a geometric series?

waxen pendant
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a/1-r

vale wigeon
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parentheses.

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a/(1-r)

waxen pendant
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yes

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so I got

vale wigeon
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what is your first term and what is your ratio

waxen pendant
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(-1/3)/(1--(3/4)

vale wigeon
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the value of $\frac{(-3)^{n-1}}{4^n}$ at $n=1$ is not $-\frac13$.

ocean sealBOT
waxen pendant
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so ur saying the first term is not -1/3

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-(1/3)

echo python
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how would I solve this equation p * (1 - p) = 0.1224?

gray isle
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yes, its not -1/3. how did you get -1/3?

waxen pendant
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-3^-1

gray isle
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where did that come from?

waxen pendant
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can we go in a voice channel please

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But if not okay

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so I broke up

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(-3)^(n-1)

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which is

gray isle
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you're over complicating this

waxen pendant
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-3^n*-3^-1

gray isle
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to get the first term
simply sub n=1 into your summand

waxen pendant
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why would u substiture n=1

gray isle
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because the index of your series starts at n=1

waxen pendant
gray isle
waxen pendant
ocean sealBOT
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Chai T. Rex

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Chai T. Rex

gray isle
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this does not mean the first term is -1/3

waxen pendant
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a/(1-r)

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a is the first term ?

gray isle
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yes, a would represent the first term

waxen pendant
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I see my mistake im used to just plugging in the number outside

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but that usually works because the other number is to the power of n-1

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is in reality it is (-1/3)*(-3/4)

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okay thank you guys so much

lost geyser
steel scaffold
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is my method correct?
18) If x⊗y = (xy)^(1/2) then what is the value of (3⊗48)⊗9 ?
(3⊗48) = sqrt(144) = 12
(12⊗9) = sqrt(108) = 10.39230485
(12⊗9) = 6sqrt(3)

ionic jewel
willow bluff
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Someone please dm me and help🥶

hasty hound
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,rotate

ocean sealBOT
rich basin
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Would anyone be able to please help me

rich basin
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I need help with c

sullen nova
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yo

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can someone explain me this?

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<@&286206848099549185>

rich basin
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@sullen nova Would you be able to help me, looks like you are ahead in the exponential part

sullen nova
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show me ur ans on A and B

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@rich basin

rich basin
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So this is how far in it that I have

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I derived the slope at the point -1/2,2 1/4 in the function

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which the equation for the tangent at that point is y=3x+15/4

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and I have the normal tangent that collides with point B the equation being y=(x+5)/2

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And since I know these equations, how can I find the angle

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for c

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I'm just brainstorming some ideas

sullen nova
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how do you get this?

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y=3x+15/4

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@rich basin

rich basin
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I got y =3x+15/4 through finding the derivative at the point of -1/2 in the parabola

shell widget
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@sullen nova dy/dx = -ay, rearranging, we have dy/y = -a dx, integrating both sides, we get ln(y) = -ax + k, which is just e^(-ax + k) = y, which is just y = e^(-ax) * e^k

sullen nova
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this is the formula to find an angle made between 2 lines

shell widget
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e^k is just a constant, so let it be A

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so you get y = Ae^(-ax)

rich basin
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I still didn't get it correctly

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this is not the soluton

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the answer for that is 45 degrees. But got it incorrect

sullen nova
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so you got 45 deg?

rich basin
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No

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So when i evaluate it into tan() = 1

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I got 0.78

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The answer is 45 degrees, but don't know how to get to there

sullen nova
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,w tan^-1(abs((3-1/2)/(1+3(1/2))))

rich basin
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Yeah that is what I got

sullen nova
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and it is in radian

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turn it into degreee

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it will be 45

rich basin
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Oh yeah, I'm in radian mode

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Oh nice, thanks. But where did you get that formula from

fluid valley
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hi guys !!!

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how can i produce this sequence ?

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1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1,…

vale wigeon
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are you looking for an explicit formula or something?

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am i understanding correctly that this sequence consists of steadily lengthening runs of ones and zeros?

sullen nova
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hmm

vale wigeon
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so it goes with 4 ones then 4 zeros then 5 ones then 5 zeros and so on

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is my understanding correct? @fluid valley

sullen nova
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something to do with the sin funciton

fluid valley
vale wigeon
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uh huh

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give me a moment...

fluid valley
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ok !!!

vale wigeon
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i think i got it

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$a_n = \begin{cases} 1 & n \leq \mathrm{round}(\sqrt{n})^2 \ 0 & n > \mathrm{round}(\sqrt{n})^2 \end{cases}$

ocean sealBOT
vale wigeon
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where round(x) is the function which rounds x up or down to the nearest integer, whichever is closer; for consistency you can say that it rounds half-integers (like 6.5 or 1.5 or 123.5) upward, but it doesn't matter here since sqrt(n) is never a half-integer

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@fluid valley there you go

fluid valley
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wow amazing !!! how did u figure it out ?

vale wigeon
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i noticed that the last 1 in every run was at a position that is a perfect square

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that is, the 1-runs ended at positions 1, 4, 9, 16, 25 and so on

robust fjord
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doesnt $\operatorname{round}(\sqrt{n+1})-\operatorname{floor}(\sqrt{n})$ also work?

ocean sealBOT
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Obstacle

vale wigeon
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does it?

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lemme take a look

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looks like it does! but it's shifted by 1 relative to my solution

fluid valley
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since it is sequence question there are a lot of solutions to it

thanks alot Ann

sullen nova
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first 100

#

[1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1]

#

algorithm

oak chasm
#

Start with index 1.

sullen nova
#

def gen(n):
n = n + 1
... res = []
... for i in range(n):
... if i <= round(math.sqrt(i))**2:
... res.append(1)
... else:
... res.append(0)
... return res

oak chasm
#

Note the extra 1 in front.

sullen nova
#

fixed

vale wigeon
#
you can make code blocks like this
#

```
code goes here
multiple lines possible
```

oak chasm
#

Yeah,

```python
code
code
```

For syntax highlighting.

vale wigeon
#
def gen(n):
     n = n + 1
     res = []
     for i in range(n):
             if i <= round(math.sqrt(i))**2:
                     res.append(1)
             else:
                     res.append(0)
     return res
oak chasm
#

I think that still starts with 0, though, so it has an extra leading 1.

#

How do you get the range to start with 1?

vale wigeon
#

range(1,n+1)?

sullen nova
#

yes

oak chasm
#
def gen(n):
     res = []
     for i in range(1, n + 1):
             if i <= round(math.sqrt(i))**2:
                     res.append(1)
             else:
                     res.append(0)
     return res
sullen nova
#

i believe we can also use pascal for this

vale wigeon
#

you can write an algorithm in basically any language for this

#

even brainfuck if youre so inclined

sullen nova
#

not pascal as a language

#

the pascal formual

vale wigeon
#

the what now

vestal needle
#

could I get some help with this?

shell widget
#

whats question 22

limber ledge
#

good morning

vestal needle
#

this

shell widget
#

ok so try to use part a

vestal needle
#

hmmmm

#

so something like $z=\dfrac{1}{\bar{z}}$?

ocean sealBOT
elfin ibex
#

this chat aint occupied

#

hey anyone know how to start this?

vestal needle
#

@elfin ibex what do u need help with? simplify it?

elfin ibex
#

yeah ^^

vestal needle
#

do u know how to simplify surds?

elfin ibex
#

surds?

vestal needle
#

$sqrt{a}$

ocean sealBOT
vale wigeon
#

$\sqrt{a}$

ocean sealBOT
vale wigeon
#

roots

elfin ibex
#

yeah

vestal needle
#

damn

elfin ibex
#

i just dont know how to find the prime factor thing

vale wigeon
#

factor 45 and 80

#

what's giving you trouble w/ doing that?

elfin ibex
#

idk..

#

i just dont know how

#

like how do u find it easier

vale wigeon
#

do you know how to factor numbers in general

vestal needle
#

@elfin ibex are there any perfect squares that 45 and 80 are divisible by?

elfin ibex
#

i just keep putting random numbers into my calculator

vale wigeon
#

5 is not a perfect square

vestal needle
#

^

vale wigeon
#

but 45 is divisible by 5

#

and 80 is also divisible by 5, by coincidence

#

45 = 3 * 3 * 5 and 80 = 2 * 2 * 2 * 2 * 5

#

these are the prime factorizations

#

look up "how to factor numbers into primes"

elfin ibex
#

but 3 isnt a perfect square

#

niether is 2 or 5 ;-;

vestal needle
#

thats the prime factorisation of 45 and 80

#

then you can break up the square root

vale wigeon
#

2, 3 and 5 are primes

#

but i can also write this as

#

$\sqrt{45} = \sqrt{3^2 \cdot 5}$

ocean sealBOT
vale wigeon
#

and $\sqrt{80} = \sqrt{4^2 \cdot 5}$

ocean sealBOT
elfin ibex
vestal needle
#

@elfin ibex to simplify surds look for perfect squares that the number inside the surd is divisible by

elfin ibex
#

but what perfect square is 45 divisible by

vestal needle
#

9

elfin ibex
#

ohh

#

so what do i do next?

vestal needle
elfin ibex
vestal needle
#

here read this

#

$2\sqrt{45}-\dfrac{1}{2}\sqrt{80}=2\sqrt{9\times 5}-\dfrac{1}{2}\sqrt{16\times 5}$

ocean sealBOT
graceful lance
vestal needle
#

and then you can take split the surd and the perfect square using the rule that $\sqrt{ab}=\sqrt{a}\times\sqrt{b}$

ocean sealBOT
elfin ibex
#

okay.....

vestal needle
#

you should probably watch a video on youtube on how to simplify surds

elfin ibex
#

i tried

#

they didnt help

elfin ibex
#

@~~@

#

idk what surds are

#

im just here to simplify a square root

vestal needle
#

square root are surds

elfin ibex
#

alr for this eqution

vestal needle
#

square root is the symbol

elfin ibex
#

would a perfect square

#

be

#

9

#

for 90

vestal needle
#

for which number?

#

yes

#

correct

elfin ibex
#

for 10 what would it be?

vestal needle
#

is 10 divisible by a perfect square?

elfin ibex
#

no

vestal needle
#

then its already simplified

elfin ibex
#

oh

vestal needle
#

you cant simplify $\sqrt{10}$ further

elfin ibex
#

i always thought u had to keep dividing until u cant anymore

ocean sealBOT
elfin ibex
#

like 10/2

#

5

vestal needle
#

na

elfin ibex
#

okay thanks

vestal needle
#

nws

elfin ibex
#

so

#

now that i got 10 and 9

#

what do i do?

vestal needle
#

so now you can rewrite it as $-6\sqrt{10}+5\sqrt{90}=-6\sqrt{10}+5\sqrt{9\times 10}=-6\sqrt{10}+5\sqrt{9}\times\sqrt{10}$

ocean sealBOT
elfin ibex
#

oh

#

thats simplified then?

#

i thought it was 3 numbers

vestal needle
#

whats $\sqrt{9}$?

ocean sealBOT
elfin ibex
#

3

vestal needle
#

yes

#

so you can write it as 3

#

and then simplify further

elfin ibex
#

im gonna go die

vestal needle
#

if u still dont get it, then u should watch a video on youtube and try to understand it properly

graceful lance
#

the (iv) one

alpine sable
#

im not sure if this is the way

#

but i can try

elfin ibex
#

@alpine sable can u help me with this

alpine sable
#

uh sure

#

i will try my best!

elfin ibex
#

can i dm u?

graceful lance
elfin ibex
#

oh

alpine sable
#

right?

alpine sable
graceful lance
alpine sable
graceful lance
alpine sable
#

okay, but so just replace the values of alpha and beta

#

you should be good to go

little nebula
#

can someone help me with my exit ticket?

#

plugging in no work

vale wigeon
#

exit ticket?

#

is that like a test? or is it not timed / open-book

#

also, i see you've selected choice A. was that intentional or random?

alpine sable
#

two different definitons given for h(x)

#

but luckily this won't affect the answer

alpine sable
#

keep in mind the average rate of change of a line over any interval is equal to the slope

little nebula
#

ok

#

@alpine sable i think its A

#

it was the graph being different no wonder yi couldnt solve it

vestal hollow
#

Oops my bad

alpine sable
little nebula
#

yeah i c how to do it

#

it was just written wrong

alpine sable
worldly pike
#

Simplify ?

limpid spade
#

simplify tanxsinx first

wild shard
#

tanx and sinx make sinx^2 / cosx

#

then find a common denom

#

get sinx^2 / cosx + cos^2 / cosx

#

that simplifies to 1/cosx

vale tundra
#

Can anyone help

#

Part b

#

.-.

sullen nova
#

hello

vale tundra
#

Wait

sullen nova
#

pls halp

#

<@&286206848099549185>

vale tundra
#

Pls i am still stuck

#

Dont post over me

alpine sable
#

any free to help

vale tundra
sullen nova
#

i thin k I know

vale tundra
#

Hmm can you try to explain?

sullen nova
#

I am checking my notes

vale tundra
#

Oki take your time

alpine sable
#

How do u solve sin(x)=cos(x/2)

vale tundra
sullen nova
#

what is the line equation on the second part of the graph?

vale tundra
#

Solving

#

y=3/4x-5

vale tundra
#

Used point 40,25 and 20,10

vale tundra
#

anyone?

sullen nova
upbeat oxide
#

what is this evaluated?

sullen nova
#

@vale tundra

nocturne wolf
#

I need help, not sure if its 65 or 92

vale tundra
#

I dont know if i should risk it

sullen nova
#

don't

#

I am not sure

vale tundra
#

I will post at another time i think

sullen nova
#

my best guess is (10,-50)

indigo jetty
#

how did you get the answers for the critical points?

nocturne wolf
#

I need help

sullen nova
#

@vale tundra Trust me

woeful remnant
#

Hey everyone, the average tweet takes 10-15 seconds to type.. if a user joined Twitter in 2009 and has 70,000 tweets, how would you calculate the approx amount of time the user has spent on Twitter in total?

sullen nova
#

I am 90% sure

#

(10,-50)

vale tundra
#

How did you do it????

#

I have been stuck on this for forever

sullen nova
#

how did you get the part (a) right?

#

if you know (a) it's not hard to do (b)

vale tundra
#

I dont remember tbh

sullen nova
#

btw do you know how to do integral?

vale tundra
#

@sullen nova How about 20

#

Hmm

ocean carbon
#

Does anyone know how I am supposed to predict the velocity of a bullet moving from one starting vector to an ending vector, given a static speed value and a gravity value?

alpine sable
#

Okay so i have this question on a mock exam paper that has rlly stumped me:

Two similar solids have base areas of 47cm2 and 199cm2. The volume of the smaller solid is 350cm3, calculate the volume of the larger solid.

#

How would I go about solving this?

sullen nova
#

@vale tundra (20,-75)

alpine sable
#

anyone free to help me with some problems

ocean carbon
alpine sable
#

Uhh

#

I dont know what kind of solid it is

#

It looks to be like, halfway between a pentagonal prism and a trapezoid?

#

Hold on

ocean carbon
#

To get the distance of two vectors, could I just add them together and then get the Length of the new vector

alpine sable
#

Ugh images take forever to sent with my internet

#

Just gonna delete that because I forgot to crop it

merry nova
#

the length of the sum of two vectors is not necessarily equal to the sum of the lengths of the vectors

sullen nova
alpine sable
merry nova
#

so we need two facts:

  1. if you scale a 2 dimensional figure by a scale factor k, the area changes by a factor of k^2
  2. if you scale a 3 dimensional figure by a scale factor k, the volume changes by a factor of k^3
#

we are given the these two figures are similar, so one must have been formed by scaling the other

#

in particular the two bases are also similar

#

assume the scale factor is k

alpine sable
#

that makes sense

#

lemme just

#

nvm Idk how to calculate the scale factor of 2d shapes

merry nova
#

so write an equation relating the two areas

#

(area of base on left)*(k^2)=(area of base on right)

#

then solve

alpine sable
#

so l*k^2=r?

merry nova
#

what is r and I?

alpine sable
#

left and right

merry nova
#

yes

alpine sable
#

ok...

vale tundra
alpine sable
#

so to make k^2 the subject id need to add r to both sides, and divide by k^2?

vale tundra
#

Thank you so much

merry nova
#

47k^2=199

#

divide by 47

#

then take the square root

alpine sable
#

ohh that makes more sense

#

199/47 is 4.234, sqrt(4.234)= 2.057

#

thats k, so that means k^3=8.712

merry nova
#

yes

alpine sable
#

which is the scale factor for the volume

merry nova
#

yep

alpine sable
#

350*8.712= 3049.305

#

NICE

#

tyvm

vale tundra
#

Anyone?

alpine sable
#

that is far beyond my area of knowledge lmao

#

shut

merry nova
#

where did you get -30

vale tundra
merry nova
#

do you know why you got the x coord to be 4

vale tundra
merry nova
#

cool

#

$G(t)=G(0)+\int_{0}^{t}G'(s)ds$

ocean sealBOT
#

AAAAAAAAAAAAAAAAAAAA

merry nova
#

so plug in t=4 and compute

vale tundra
#

Ohhh

merry nova
#

btw this comes from rearranging

#

$\int_0^t G'(s) ds = G(t)-G(0)$

ocean sealBOT
#

AAAAAAAAAAAAAAAAAAAA

vale tundra
#

So i need to find G(4)

merry nova
#

yes

vale tundra
#

-8+ 1/2*-4x2

#

For the f

merry nova
#

for the integral part yes

#

you also need to add in the initial condition

vale tundra
#

so 18

#

Ayyyy

#

Thank you

stable dune
#

im not sure about this could you help me?

alpine sable
#

a^2 + b^2 = c^2

#

With C being the hypotenuse, and A being the length

#

To work out b, you need to work out c^2, and take a^2 from it

#

@stable dune

stable dune
#

so

#

5^2 + b^2=13^2

#

25+b^2=169

#

but how can i figure out b^2 now

alpine sable
#

Take 25 fro 169

#

And that gives you b^2

#

Then take the square root of that number and you have your answer

stable dune
#

ah okay'

#

i subtracted 169 and 25

#

i got 144

#

now doing the square root

#

i got 12

alpine sable
#

I have that number burned into my memory lmao

#

12*12 = 144

stable dune
#

lmao

#

right

alpine sable
#

Your answer is 12

#

So C

stable dune
#

what about this

#

a^2+b^2=c^2

#

right?

alpine sable
#

Well, this is just worded differently

#

The base of the house is 6ft, which means the base of the triangle is 3ft

#

The hypotenuse is 5ft

#

Just plug those into the formula, just like before

stable dune
#

hm

#

6^2+3^2=5^2?

alpine sable
#

No

#

3^2 + b^2 = 5^2

#

You are solving for B

stable dune
#

ah but whats 6?

alpine sable
#

Okay

#

The house is made up of two right angle triangles

stable dune
#

right

alpine sable
#

The problem tells us that the base of the entire house is 6ft

#

Which means the base of both triangles is 3ft

#

Considering that the hypotenuse is equal for both, and they share the same height

#

And as you are trying to find the height, you need to use 3ft instead of 6ft

stable dune
#

ohhh

#

4?

alpine sable
#

Idk, you are the one working it out

stable dune
#

thats what i got after figuring out i got 14

alpine sable
#

Does anyone have any idea how Im supposed to go about solving this question?

stable dune
#

square root of 14 is is 4

young pier
#

lol

alpine sable
#

No, its not

#

Square root of 16 is 4, but not the sqrt of 14

velvet pelican
alpine sable
#

Nope

#

Not for finding y, at least

velvet pelican
#

Have you heard of circle theorems?

alpine sable
#

I can find x if I have y

#

Yes, I have

velvet pelican
#

You can find x using the cyclic quadrilateral one

#

then use the angle at the centre theorem

alpine sable
#

Ohhhh

#

That makes much more sense

#

But id need to know BAD and DCB for that

#

Wouldnt I?

velvet pelican
#

What does the cyclic quadrilateral theorem say?

alpine sable
#

Wait no

#

Just remembered

#

ADC + ABC = 18P

#

180*

velvet pelican
#

Yes

alpine sable
#

I remember now

#

Thanks

velvet pelican
#

Welcome

halcyon cloud
#

can anyone help me with this, its not a test

alpine sable
#

A) is simple trigonometry, just scroll up and ive already explained how to do it

#

B) i actually suck at trigonometry so I couldnt tell you

stable dune
#

im not sure ab this

rigid gyro
#

I know how to do

stable dune
#

can you explain

#

ik its a^2+b^2=c^2

#

but is it 10^2+b^2=26^2?

rigid gyro
#

Yeah so c is always the longest side

#

Yes

glass solstice
#

uhh

#

i have a question

#

how do i do this

rigid gyro
#

Oh that

glass solstice
#

yeah

rigid gyro
#

I forget how to do that

glass solstice
#

oh

#

dont i subsitute n for 10

rough spear
#

I think I can help

glass solstice
#

and then do av9*3

#

oh

#

great

#

bc im stuck

rough spear
#

a_1 is 10

#

you substitute n for the other terms

glass solstice
#

oh

rough spear
#

so a_2 will be the second term

#

a_3 third

glass solstice
#

ohh

#

so for n it would be the term

rough spear
#

so to find the second term

#

yes

glass solstice
#

ohh

#

and u subtract 1

#

bc its the formula

rough spear
#

$a_2=a_{2-1}×3$

#

yes

stable dune
halcyon cloud
#

can anyone help me with this

ocean sealBOT
#

nintendo

halcyon cloud
glass solstice
#

thanks

rough spear
#

no big

#

@halcyon cloud what have you tried

halcyon cloud
#

wym

stable dune
rough spear
#

like what has been your attempt so far in getting the solution

halcyon cloud
#

not much ive been absent for the past few classes and im not sure where to start

rough spear
#

I see

#

do you know the Pythagoras theorem

halcyon cloud
#

yh

rough spear
#

hyp²=adj²+opp²

#

that's what you use for a

#

do you know what side we're looking for here?

halcyon cloud
#

so im solving for hypotenuse right

#

the longest side?

vast ether
rough spear
#

no

#

you have the longest side

halcyon cloud
#

yea @vast ether

#

oh

rough spear
#

the part the ladder touches the building

#

to the ground

#

that distance

halcyon cloud
#

so how would i solve for that

rough spear
#

since you have the hypotenuse and the adjacent you just plug in the values for Pythagoras

#

then change the subject formula to find the opposite

#

since that's what we're looking for here

halcyon cloud
#

so hyp - adj = opp

#

thats what im doing right

rough spear
#

yes

#

don't forget the square

halcyon cloud
#

ok so isnt that 5 squared?

#

wait

#

im doing 10^2 - 5^2?

rough spear
#

10²=5²+opp²
10²-5²=opp²

vast ether
halcyon cloud
#

so 5√3 radical

#

so what abt the values?

#

wait i have an idea

vast ether
#

If you need help with part b lmk

halcyon cloud
#

ye i need help

vast ether
#

Do you know how to use trigonometric ratios?

halcyon cloud
#

looks good?

#

@vast ether

alpine sable
#

yo tiggle u tryna copy me?

vast ether
vast ether
alpine sable
#

i think u are the imposter

#

im SPONGEBOB

halcyon cloud
#

i dont know what to do honestly @vast ether

#

and theres other questions

vast ether
#

Stop twerkin' my square booty

vast ether
alpine sable
#

yo tiggle yk who we hate

vast ether
#

D: Doodlebob