#help-0

1 messages · Page 871 of 1

normal minnow
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its basically functions like finding range and domain of composites and skipping sets as well as sketching functions given information

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and cuz our teacher really wants us to take precalc we have the difference quotient

glass lichen
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channel's in use unless alvan's done

normal minnow
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okay

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sorry

glass lichen
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in use

alpine sable
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sorry

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but NervousSweat is it correct ?

pulsar lark
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6^2-4(k+3)(-1)=triangle sign?

glass lichen
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Delta, but yes

pulsar lark
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36+4k+12=delta
48+4k=delta

slim spire
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I guess x_g > x_1?

pulsar lark
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I stuck at here

glass lichen
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-4*k is 4k?

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didnt know

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oh wait

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nvm, forgot it was -1

pulsar lark
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So i am right so far?

glass lichen
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yes

pulsar lark
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What should i do next?

glass lichen
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wdym

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you're done part a...

pulsar lark
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Really?

glass lichen
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...

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Yes

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A wants a function of k for the discriminant...

pulsar lark
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I thought it want me to find k

glass lichen
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??

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that's part b

pulsar lark
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Ok

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Give me some time to do

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Forget it,i am stuck

slim spire
pulsar lark
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48+4k

slim spire
slim spire
pulsar lark
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But how about part b

wary stream
slim spire
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Part b is the same as before!
The discriminant Δ of a polynomial is used to tell you if there is 0,1 or 2 real roots and how to compute them ok?
For instance if Δ<0, then there are no real roots, if Δ=1 there is only one real root and if Δ>0 there are 2 real roots

glass lichen
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"D=1"

glass lichen
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also there's not only 1 R root, it's 1 R root multiplicity 2

glass lichen
spiral perch
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Hi. How many ways can you choose a pair of compositions from white and black squares on an 8x8 board?

pulsar lark
glass lichen
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Yes

pulsar lark
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48+4k>0

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Right?

glass lichen
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yes.

slim spire
normal minnow
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well its 8*8 = 64 squares and there are two possible balck or white so im pretty sure 64!/2!

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I might be wrong

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wait i am

pulsar lark
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2^64?

alpine sable
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is the channel claimed ?

pulsar lark
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Yea

normal minnow
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its always

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claimed

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sadness

pulsar lark
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Always has been

hasty hornet
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nvm just realized i missed a step

nova raven
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Hey i have a question.

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is there any methods to finding the equation of a polynomial function given a set of points

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I am already using lagrange interpolation and just wondering if there are other methods

slim spire
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@nova raven The polynomials are unique, so I don't think so

nova raven
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ahh so just that kk thansk

slim spire
# nova raven ahh so just that kk thansk

But there are other (smarter) ways to interpolate! Lagrange polynomial is not really stable (try changing a little some values and you will get another completely different polynomial)

nova raven
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thats true i did see that

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what are these smarter ways

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@slim spire

slim spire
nova raven
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ok but would that work for a polynomial

slim spire
pulsar lark
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Question 1a What should I do?

nova raven
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you can use that and solve for k

pulsar lark
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Ok

fallen plank
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channel taken

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?

pulsar lark
nova raven
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i was pretty much done

slim spire
thorn kindle
fallen plank
# nova raven kind off but i dont mind

A lattice point in a rectangular coordinate plane is a point both of whose coordinates are integers. How many lattice points are there on a circle that is the graph of the equation x2+y2=625?

slim spire
fallen plank
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wdym <=, it's just =

thorn kindle
fallen plank
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yes

thorn kindle
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Sqrt625?

fallen plank
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25

slim spire
# fallen plank how

as y^2≥0 then x^2≤x^2+y^2≤625 hence x≤25 and similarly y≤25, so you "only" have to try for x,y smaller than 25 lol

thorn kindle
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True. But you wrote it weird

slim spire
thorn kindle
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Consider the points upon the axes first

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4 of them

fallen plank
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i can think of a couple lattice points off the top of my head: (0,25), (25,0), (0,-25), (-25,0)

slim spire
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Then x^2+y^2=625 you could proceed the same: write a list of square for n=0 to 25 and try to find any pair that sums to 625

fallen plank
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there has to be an easier mehtod

slim spire
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Surely haha

fallen plank
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instead of guess and check

thorn kindle
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There is only one pair

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And you will multiply that by 8

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You should have 12 solutions

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Thats it lol

fallen plank
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wdym there is only 1 pair

thorn kindle
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That's all the question asks. Not for the actual values

fallen plank
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i have to show my work btw

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i can't just give an answer out of thin air

slim spire
thorn kindle
fallen plank
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(20,15) works i think

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but how do you know that's it

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how do you know there's nothing else

thorn kindle
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Two solutions in each quadrant plus two on each axis

fallen plank
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so in the 1st quadrant it would be (20,15), (15,20)?

slim spire
fallen plank
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2nd - (-20,15), (-15,20)?

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3rd - (-20,-15), (-15,-20)

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4th - (15,-20), (20,-15)

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??

pulsar lark
thorn kindle
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Wait my bad. You also have to consider non primitive triples. 15 and 20, AND 7 and 24

fallen plank
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oh so you're thinking about it as a right triangle?

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pythagorean triplets - a multiple of 3-4-5 is 15-20-25

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and 7-24-25 is also an answer

pulsar lark
slim spire
fallen plank
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bc 8 solutions for 7-24-25, 8 solutions for 15-20-25, and 4 solutions for the axis points?

pulsar lark
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@slim spire nothing now

fallen plank
thorn kindle
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Yep

fallen plank
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PHEW

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TY

pulsar lark
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@slim spire still don’t understand.

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What should i find first?

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😩😩😩😩

slim spire
pulsar lark
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So part a, (-8)^2-4(2)(3k) is delta?

slim spire
pulsar lark
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Not yet

slim spire
slim spire
# pulsar lark K=3/8

You missed a solution! In fact there is one more ... Solution: ||Δ=64k^24k=8k(8k-3)=0 hence k=0 or k=3/8||

harsh belfry
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Could I jump in to ask a calc question?

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Or is this channel still in use?

pulsar lark
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You can

harsh belfry
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Thanks

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I tried to do this problem but I've been having some issues.

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I thought I could start by finding the slope by calculating the derivative of the given equation.

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I ended up getting

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I input this into a y=mx+b equation where

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Then I solved for b.

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But I keep getting the wrong answer on all of my submissions.

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Not too sure what to do or if I did the wrong thing in the first place.

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This was the equation I used.

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Would I insert 1/2 in for x?

supple tundra
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You need to two things

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The gradient of the curve at the point x = 0.5

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You've found the gradient function, so just sub x = 0.5 for the gradient/slope at that point

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and you can use this equation for the line

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$y-y_1 = m(x-x_1)$

ocean sealBOT
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azeem321

supple tundra
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Where $(x_1,y_1)$ is a point on that line

ocean sealBOT
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azeem321

harsh belfry
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I'm a little confused, so would I instead solve for

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then take that value and input it into the equation above?

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ah wait give me a monet I think I get it now

supple tundra
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Do you get that the derivative gives you a gradient/slope function? It allows you to find the slope at any point on the original curve?

harsh belfry
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Would I insert 0 as y

harsh belfry
supple tundra
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For the equation of a line $y = mx + c$ what does $m$ mean?

ocean sealBOT
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azeem321

harsh belfry
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M is slope.

supple tundra
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Right. And you have a slope function here $\frac{3}{\sqrt{1-x^2}}$

ocean sealBOT
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azeem321

supple tundra
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Which means you can substitute any value of $x$ for which it is defined

ocean sealBOT
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azeem321

supple tundra
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and get the slope at that point

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Wait

harsh belfry
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I'm sorry if I'm not following but in that case would this be true?

supple tundra
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Yes

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and that will give you the slope

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at x = 0.5

harsh belfry
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would be my equation then

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solving for b

supple tundra
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Yes, but it would be better to use the exact form instead of the decimal form

harsh belfry
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gives me

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−0.16125447

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for my b

supple tundra
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That's probably correct, but it's better to use the exact form because exam questions usually ask for exact form instead of as decimal

harsh belfry
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Yes I was about to say that

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I used my calculator for that.

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I'll have to solve for it manually then.

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Thanks for the help azeem

supple tundra
harsh belfry
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Hey

strange raven
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Hi

harsh belfry
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I'm sorry to bother you @supple tundra

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But I did write this correctly right?

strange raven
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123 which are natural numbers also come under the umbrella of real numbers right?

harsh belfry
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It appears to be incorrect still.

flat ermine
strange raven
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@flat ermine thankyou

harsh belfry
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Maybe I have the wrong B value

supple tundra
# harsh belfry

You must substitute x=0.5 into $\frac{3}{\sqrt{1-x^2}}$ and that will give you the m they want

ocean sealBOT
#

azeem321

harsh belfry
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ah they would want this then

supple tundra
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correct

harsh belfry
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very weird to me

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thanks again

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Ah i guess the B is incorrect if you change the value of X

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I see

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Nevermind.

atomic lodge
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Can anyone help me understand what’s concave up and down

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Like I know the shape of the graphs but I am confused

supple tundra
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Never liked that concave up, concave down stuff. Basically, if a function's derivative is increasing over an interval, then it would be like a positive quadratic on that interval which is concave up or some call it convex. If a function's derivative is decreasing on an interval, then function would called concave down or just concave

grim delta
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thats one of the many things i did in Calc 1 and then promptly forgot about

supple tundra
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Note that, if a function's derivative is increasing, it doesn't necessarily mean that it's derivative is positive

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It just means the slope of the function is increasing or becoming less negative

atomic lodge
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Thank You for your help!! @supple tundra

supple tundra
pulsar lark
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Can i use the channel?

supple tundra
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ya

pulsar lark
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Thx

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How to solve Question (a)?

supple tundra
robust geode
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You know that real and imaginary numbers can never be melted in order to make a single number, right?

pulsar lark
lapis sluice
wary stream
# pulsar lark How to solve Question (a)?

Because it's an equation that means the LHS equals the RHS, so that means you can set the real terms equal to each other and the imaginary terms equal to each other

pulsar lark
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So 2x wont be -yi?

robust geode
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Just know that i is just here in order for you to k ow that the number by which it is multiplied has an other purpose than the other number

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The imaginary part is real, as much as the real part

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It's just that the imaginary part is always what's being multiplied by i

wary stream
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But that's with magnitude

robust geode
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I'm not checking any single piece of rigourosity for his own understanding

pulsar lark
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Ha?

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Ok, so x=4, y=-5?

robust geode
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Yup good job

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You got it

pulsar lark
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But how do i express it?

wary stream
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Exactly like how you did

robust geode
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Just use a factorisation

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As you have normally done before

pulsar lark
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Just like this?

robust geode
#

Could we talk in vc maybe?

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It will be easier to explain if I talk lol

pulsar lark
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I cant speak English…

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But i can listen

robust geode
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I will try my best in order to not have an accent and be as clear as possible

wary stream
crisp widget
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Can someone help me?

quasi lodge
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anyone can help e

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me

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grade 8

full marsh
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@quasi lodge not unless you send question

quasi lodge
brittle steeple
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heyy can someone help me rq

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and tell me what this means

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you can also just tell me the answer and I can make a pretty good guess how u got it

azure jungle
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Derivation. Derivate it once. Number 3, task a) and f)

wary stream
brittle steeple
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okay then can you give me a hint on what the heck the two means

wary stream
#

Use log properties

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And that 2 is an exponent

azure jungle
brittle steeple
#

so its log, base 3 1/3 squared?

wary stream
#

,rotate

ocean sealBOT
brittle steeple
#

@stable basin thanks luv u <3

wary stream
azure jungle
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can u help me dldh06 ?

wary stream
#

What's the goal?

azure jungle
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need help on number 3 task a and f, idk how to derivate it

brittle steeple
wary stream
wary stream
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Do you know power rule, chain rule, product rule?

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Because you need the knowledge of all three to do those questions

azure jungle
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we were not taught any power rules that i see on the net, we were only learned taught this f(x) = uv(x) + v(x) so it means f´(x) = u´(x) + v´(x)

brittle steeple
azure jungle
wary stream
azure jungle
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better said, idk what to do with the last number

ocean sealBOT
#

dldh06

wary stream
#

That concept

azure jungle
azure jungle
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in a) its +3

wary stream
#

It's a constant

azure jungle
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4x^2 will be 42x

wary stream
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Derivative of constant is 0

azure jungle
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so it just "dissapears" ?

wary stream
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Yes

azure jungle
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ahh

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what about f) tho ? i never saw that task as an example

wary stream
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It's just applying all the derivative concepts, like power rule, product, and chain rule

worn prawn
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Hello can someone show me how to do these

azure jungle
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1 more question.

in task a) at 8x, the derived version is 8 times 1 and thats it ? x dissapears ? or do i do 8 times 1 times x^0 or 8 times 1 times x^-1

alpine sable
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use this

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i dont rly know the name of it in english but im sure you know what this is

worn prawn
#

Asks for ac method:'(

alpine sable
azure jungle
#

this is correct,yes ?

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i still don't understand the brackets in derivation... do i have to solve the bracket before derivation ? like, what's the rule here

wary stream
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Chain rule

azure jungle
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but we didnt learn that

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wth

raw shard
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you don’t need to use it

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you could just expand it

wary stream
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That too

raw shard
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which they did

azure jungle
# raw shard you could just expand it

how did they expand it ? i was sick that day so i could just write everything from a friend.. idk why is there suddenly -12x in the bracket and why is it +9 instead of -9

wary stream
#

Because $(2x - 3)^2 = (2x-3)(2x-3)$

ocean sealBOT
#

dldh06

wary stream
#

Then you FOIL

azure jungle
#

we were only taught
Derivation rule for power function
Derivation rule for products
and
Derivation rule for sums

raw shard
#

do you know how to expand something like (x+y)^2

azure jungle
azure jungle
wary stream
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That's what quantum was referring to, too

azure jungle
#

okay, let me try to solve 3 d) and i will show you the results, could you tell me i got it correct, please ?

raw shard
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yeah

alpine sable
#

can someone tell me why the first condition is impossible

sand geode
#

hi @alpine sable

alpine sable
#

hi

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i need some help in proofs and logic

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is there anyone active?

sand geode
#

@alpine sable em que quadrante encontramos o x-pi/3?

alpine sable
#

(p or q ) and r
if p=F
q=T
r=T

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I did long division and synthetic division and it says this is incorrect

azure jungle
#

please tell me im correct

raw shard
#

i don’t know what the second to last line says

azure jungle
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16x^2 + 12x * 12x + 9

alpine sable
raw shard
#

that’s wrong

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it’s 16x^2 + 24x + 9

sand geode
alpine sable
sand geode
#

tem certeza?

alpine sable
#

quase certeza

azure jungle
# raw shard it’s 16x^2 + 24x + 9

24x ? but it
(4x + 3) * (4x + 3)
i have to multiply first number in the first bracket with both numbers in the second bracket
and then multiply the second number from the first bracket with the both numbers in the second bracket
so : 4x times 4x is 16x^2 + 4x times 3 which is 12x, so 16x^2 + 12x so far
then 3 times 4x which is again, 12x and 3 times 3, which is 9
so 12x + 9
all together it's : 16x^2 + 12x * 12x + 9
so derivation comes in play now:
32x + 12 * 12

how do you get 24x

teal sun
#

i need help

alpine sable
teal sun
raw shard
#

@azure jungle (a+b)^2 = a^2 + 2ab + b^2

azure jungle
#

omg im so dumb

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tnx

raw shard
#

no problem

alpine sable
#

:) obrigado

azure jungle
#

sry 1 last question, how do you get 16x^2

raw shard
#

@azure jungle you didn’t do (4x)^2

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you only did 4x^2

azure jungle
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does every x number has to be in brackets ?

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when expanding

raw shard
#

what do you mean

alpine sable
# azure jungle

Not tryna be rude but i cant understand some of that hand writing

nocturne gazelle
#

F

raw shard
#

the only thing that looks weird to me is the 9

azure jungle
azure jungle
alpine sable
#

Anyone wanna help me multiply 3(4) i reallly dontntntntn know

azure jungle
alpine sable
#

It might be 405

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Idk tho

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Somebody said it was 12

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They lying

hasty hornet
#

An astronomer suggests that on average 1.31 meteorites strike the earth per month. We assume that the number of meteorites that strike the earth per month follows a Poisson distribution. Find the probability of having no meteorite strikes in a month.
Is 1.0686 correct?

flat ermine
#

1.0686 is bigger than 1

hasty hornet
#

idk anything lol

flat ermine
#

so it cant be right since a probability cant be bigger than 1

hasty hornet
#

oh yea

azure jungle
raw shard
#

yes

azure jungle
# raw shard yes

why the brackets ? how do i know when do i have to use the brackets ?

raw shard
#

you have to square 4x

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not just square x and multiply it by 4

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wait this channel is in use

azure jungle
#

i got it now, thanks a lot man, really helped me out :))

flat ermine
ocean sealBOT
#

roobix

flat ermine
#

idk how you got 1.0686 but you should use that; (\lambda) is the number of average occurrences

ocean sealBOT
#

roobix

hasty hornet
#

thanks

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what is k?

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i followed this before lol

flat ermine
#

basically same as x in that picture

hasty hornet
#

ok

flat ermine
#

its how many occurrences there really are so 0 in this problem

hasty hornet
#

$1.31^{0} \cdot \frac{e^{-0}}{0!}$

flat ermine
#

i think that should be (1.31^{0}\cdot \frac{e^{-1.31}}{0!})

hasty hornet
#

whoops

ocean sealBOT
#

roobix

lapis sluice
#

can you end a task with $\blacksquare$ when you havent proved anything, but only answered the task?

ocean sealBOT
#

Danajax

flat ermine
hasty hornet
#

does it mean multiply

lapis sluice
#

means multiply

hasty hornet
#

ty

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woo i did it

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answer is 0.2698200564

alpine sable
#

question is there a math promblem that isnt solved

flat ermine
atomic dune
#

i feel kind of stupid for asking this but I always sucked at factoring and I'm not sure how they factored 10(x-5) from this. I can see how the (x-5) would get pulled out but I'm beyond lost as to how they got that answer. Sorry if this is a dumb question but my brain is fried 😅

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I'm also really not sure where the 10 before (x-5) came from

civic jungle
#

I think many steps were skipped

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It was inviting you to do the algebraic computation yourself probably

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Solutions that do that are promoting reader independence

vale sapphire
#

and in the second term, the 10x-10 is divisible by 10 also, so you can factor a 10 there as well

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then notice that in both terms you have an (x-5), so you can factor that

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just like 4*2+4*9 = 4*(2+9) because there's a 4 multiplying both terms

atomic dune
#

oh holy shit yeah you're right, let me give it a shot from here. I can't believe I missed that

rain mason
#

can someone help with this?

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i'm pretty sure that the curvatures are all the same and the tangent vectors can be one of two opposite vectors but i don't know where to start or how to prove that

past sundial
#

When they mean x is 5 times as many as y does it mean 5x=y

vale sapphire
#

yes

muted kite
#

"If log4 3 = x, then in terms find log8 72".

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How do I solve this?

raw shard
#

@muted kite i can maybe help although i might be bad at explaining it

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so you have log4(3) = x, this also means 1/log3(4) = x

muted kite
#

the inverse of the log flips the base and argument?

raw shard
#

we can do 1.5/1.5 * 1/log3(4) = x

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yes

muted kite
#

I never knew that

raw shard
#

so that turns to 1.5 * 1/log3(8)

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then that turns to 1.5 * log8(3) = log8(3^1.5)

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now they have the same base

muted kite
#

reduce

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I don't get it fully but I'll try to write it down on my paper and see if I can get a better understanding

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I get the order

raw shard
#

you can test it with log3(9)

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the base flip

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now i’m actually not sure what to to from here, i just thought doing this would help

muted kite
#

it did help, thank you very much 😃

raw shard
#

no problem

muted kite
#

I just needed a little guidance like this to get me started

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much appreciated

cursive cobalt
#

I'm not good with logs

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🥴

muted kite
raw shard
#

no

muted kite
#

wait wait

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no

raw shard
#

4^1.5 is 8

muted kite
#

I was thinking multiplication whoops

raw shard
#

i did that to get the same base

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lol

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@muted kite actually i think it would be better it the base was 64

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because then it would be only integers

muted kite
#

oh I see

muted kite
#

or am I thinking of something wrong

raw shard
#

remember if you have n*loga(b), that equals loga(b^n)

#

can you explain your question more?

muted kite
raw shard
#

yeah

muted kite
#

I was wondering how the denominator become 1 instead of 1.5

raw shard
#

so we started with 1.5/1.5 * log4(3)

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which is the same as 1.5/1.5 * 1/log3(4)

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so multiply the two denominators

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it turns to 1.5 * 1/log3(8), or 1.5 * log8(3)

muted kite
#

ooooooh

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I was putting 1.5 and 1/log together

#

I forgot I could separate them and then reciprocate just 1/log

#

im so dumb lmao

raw shard
#

lol

muted kite
#

ty for clarifying that

raw shard
#

no problem

#

remember to change the base to 64

#

so it’s all integers

muted kite
#

ok, tysm for your help

#

I'll leave you alone and work on this

raw shard
#

ok, if you need help you can ask more questions of course

rain mason
#

can someone help with this?
i'm pretty sure that the curvatures are all the same and the tangent vectors can be one of two opposite vectors but i don't know where to start or how to prove that

slim spire
#

What is the definition of tangeant vectors and curvatures?

rain mason
#

the unit tangent vector is the unit vector tangent to the curve at that point and the curvature is |dT/ds|

#

where s is the arclength function and T is the unit tangent vector function

#

wait are you asking because you don't know or because you want to help lol

slim spire
#

Unit tangeant vectors doesn't depend on speed at which you go

hollow cedar
#

is it

#

18x^2 -9

#

?

vale sapphire
#

it is, but this has to be one of the strangest ways i've seen someone convey a question

small bear
#

No, is having 90% chance at 2 tries the same as 180% chance the first try?

#

What are you given? The probability that you can get something in 4 tries is 5%?

rain mason
#

take 1 minus the probability that you will fail every time

#

so 1 - (95/100)^4 i think

#

the possibility that it will happen at all (i.e. be triggered at least once) is about 0.1855

#

i don't think so i just thought it up

small bear
#

Complementary probability perhaps

#

Probability

rain mason
#

<@&286206848099549185> i've asked this question for like an hour and i haven't gotten any responses

rich basin
#

(b)

#

I tried multiplying point B by i because there is a 90 percent rotation anti clockwise, but it doesn't seem to work

slim spire
#

Because its 90° anti clockwise rotation but not centered at (0,0) !!!!

#

Try first to compute the vector AB as asked :p

rich basin
#

Oh right, this is not a 90 percent clockwise from the O origin

#

so it wouldn't work

#

@slim spire Is this right?

slim spire
#

Exactly!!

rich basin
#

@slim spire oh right I did it a different way and managed to get the answer

#

Okay thanks

slim spire
#

There is always multiple ways to find the answer ;p

rich basin
#

What is the fastest way?

slim spire
#

It's a fun exercise to try to find other ways of thinking haha

rich basin
#

yeah

slim spire
#

I dont see faster than computing AB to find the coordinates C or D 🤔

rich basin
#

wait how would you find D?

#

i think what i did was times i by B

#

and then added the vector B-A

#

Which doesn't seem to make sense given that Bi shouldn't be equal to C

slim spire
#

Compute vector AB -> -5+12i and rotate it 90° by multiplying by i -> -12-5i and add to A -> -3-4i

rich basin
#

why did you rotate AB?

worthy adder
#

how to find the x-intercept of x^4-8x^2+8=0

slim spire
green thicket
#

this isn't really a question about a math problem

#

but I wanted to ask

#

how long would it take

#

to learn how to factor polynomials

#

I'm really bad at it and I have about 2 hours to study since I might take a retake for the quiz tomorrow

#

but I might take the retake on Wednesday if 2 hours to learn it isn't enough

placid zinc
#

Any polynomials? Or quadratics?

#

I mean start, imo. Get on YouTube and learn haha

glass tree
#

Help? Not needed for homework or anything, I'm just making something that requires a solution to this.

#

Or more specifically, define 3 of the 4 unknowns in terms of a, b, c, and the forth unknown.

green thicket
wanton spoke
#

To help out a classmate in need, the students of 9-Strontium decided to send a cash aid of $2 000. The students shared the cost equally. At the last minute, 10 students from the SSG chipped in, lowering the contribution per person by $10 for each student. How many students are there in 9-Strontium?
I have two questions for this solution:

  1. Why did he subtract 10 to c? c-10
  2. Why are we subtracting the second from the first?
glass tree
slim spire
wanton spoke
#

how did it became c-10

slim spire
slim spire
wanton spoke
#

oh i see

glass tree
#

Can someone help me with my probem? I have no idea how to do it

#

or even where to start

#

My guess is that it's a system of quadratics but idk how to solve those and I can't find anything that shows how when you have many variables

slim spire
#

Your problem seems so weird lol

#

Try factorizing using the identity (a+b)^2=a^2+b^2+2ab
Hint: you can generalize to (a+b+c)^2=a^2+b^2+c^2+2ab+2ac+2bc

#

@glass tree

glass tree
wanton spoke
slim spire
wanton spoke
#

alright, thank you!

mossy kelp
#

how would I go about solving this? not really sure where to start, im prolly overthinking it, but I'm not really sure

slim spire
#

As codf = Y then |codf|-2=3 you must choose a function whose range is less or equal to three images among the 5 of Y

#

For instance you could choose a range of only one image: a
This means I send 1->a, 2->a, 3->a and 4->a, then rng(f)={a} has size 1 where cod(f)=Y has size 5 and 1 is less or equal to 5-2=3
Hope you understand @mossy kelp

mossy kelp
#

yeah i think i understand

#

thanks

primal hatch
#

what’s 1+1

glass lichen
charred pier
#

nevermind I found out, sorry for the bother

primal hatch
toxic meadow
#

i need assistance

slim spire
#

50(1.2)=60 and 60(1.2)=72 where 1.2=120% of the population

toxic meadow
#

i did that

#

that’s why i’m so confused

#

is it broken 🤣

slim spire
#

Broken

#

As hell lol

#

Sorry @toxic meadow

toxic meadow
#

it’s all good

slate kayak
#

In comparison to 1996 the expenses rised with 63.5% in 2002. In 2007 these expenses were 19.4% more than 2002.

with how many percentage are the expenses in 2007 higher than 2002?

#

Hi idk how to do this

#

I was given formulas like new = (1+ p/100) x old

#

But idk how to use that here

slim spire
#

Use it multiple times

slate kayak
#

What is the “old” the first time then?

#

2002 vs 1996
63.5% vs 0%
?

slim spire
#

First time: in 2002 we have 163.5% the expenses of 1996
In 2007 we have 119.4% the expenses of 2002
Hence in 2007 we have 119.4% * 163.5% the expenses of 1996

slate kayak
#

Oh like that

#

Thnx

late parcel
#

Is this channel open

slate kayak
#

Yes

late parcel
#

Can someone check this

slate kayak
#

That looks like a test

late parcel
#

It’s not look at the top, it says practice

slate kayak
#

srry

slim spire
#

,w plot int_1^x 100(t^2-3t+2)e^(-t^2)dt from x=(1,3)

late parcel
#

Wait what

slim spire
#

Lol nvm

late parcel
#

They are all true right?

#

Wait

slim spire
#

🤔

#

Now think about why

late parcel
#

Wait is it actually E?

slim spire
#

e=2.718281828459045... is a nice EXPonentiation constant

late parcel
#

The letter choice E

#

1 2 and 3 are all true

slim spire
#

Lol sorry not it's II only

slim spire
# ocean seal

Check the graph it decreases from 1 to 2 and g(3)<0

late parcel
#

Wait what

#

So it’s B?

slim spire
#

Yeppp

late parcel
#

Thx

slim spire
#

Np

#

Btw true way to answer is that integral of f is increasing iff f is increasing

late parcel
#

Thank you

slim spire
#

,w (d/dt t^2-3t+2)=0

devout summit
#

Consider the function e^{-x}. It's integral is -e^{-x} which is increasing but the function is decreasing

late parcel
#

I have another question

#

57

#

Somehow the answer is A

#

This is what I have

slim spire
late parcel
#

I have the second derivative

#

But am stuck from here

slim spire
#

@late parcel concave means f''(x)<=0

late parcel
#

Yep

#

I knew that

#

But how does that help for A

#

The A is confusing me

slim spire
#

Then 6ax+6<=0 solve for x

#

,w 6ax+6<=0 solve for x

late parcel
#

How do you solve for x when there is an a

slim spire
#

Tadam

#

Think of a as a number like 5 or -5 depending on if it's positive or negative

#

Then proceed like usual

late parcel
#

What number do you use

slim spire
#

The letters represent just some numbers so think about them as numbers

late parcel
#

What number do you use

devout summit
slim spire
#

Duuuuude english is weiiiird

#

Thank you lol

#

Im so choked it is not concave and convex but anyway

late parcel
#

Umm so what number would you use

#

Anything?

devout summit
#

,w 6ax+6>0, solve for x

ocean sealBOT
shut parcel
#

$399 is what percent more than $189?

slim spire
#

The best is just to use "a" but remember it represents a number

slim spire
#

,w 399/189*100

devout summit
shut parcel
#

I got an answer of 111.11%

late parcel
#

Occupied channel

slim spire
#

Im leaving

#

I need sleep

#

Bye friends

late parcel
#

Wait

#

What about my question

#

Almost done @slim spire

#

Can’t leave me hanging like this

shut parcel
#

Wouldn’t the original price be $189?

devout summit
late parcel
#

@devout summit I get a

#

How does that help

devout summit
devout summit
ocean sealBOT
#

Euclid31415

shut parcel
#

More means add, right

devout summit
late parcel
#

Why flipped sign

shut parcel
#

Anyone else got an answer of 111.11%?

late parcel
#

You flip sign whenever you divide by a negative

#

Is that how it works

devout summit
late parcel
#

Is it divide or multiply by a negative? Or just divide @devout summit

devout summit
#

If you have x>y, ax<ay if you take a<0

shut parcel
#

You got 111.11%, right

#

Why did another person say 211.1%

late parcel
#

What

shut parcel
#

I got an answer of 111.11% but someone said the answer is 211.11% so I’m confused now

late parcel
#

Why is it A and not C

#

Couldn’t it also be C

devout summit
# late parcel What

If you multiply a negative constant on both sides of an inequality, the inequality flips

late parcel
#

Ok

#

So I think it could be A or C

#

Look at this

shut parcel
#

Hey euclid can u help me

late parcel
#

@shut parcel this channel is occupied

devout summit
late parcel
#

Ok I understand that

#

But why does C not work

#

It could go to positive infinity

devout summit
late parcel
#

Why?

devout summit
#

x<-1/a

late parcel
#

But that’s just for a critical point

#

So X is bigger than that number

devout summit
#

No! for example, $x<3\implies x\in (-\infty,3)$

ocean sealBOT
#

Euclid31415

late parcel
#

Ok correct

#

I follow that

#

Ohhhhhhhhhhhhhhh

#

I see now

#

I see

#

Thank you

shut parcel
#

So euclid lol

#

Can u help me with my hw lol

devout summit
late parcel
#

@shut parcel thanks for the patience, good luck with your problem

shut parcel
#

Thank u misty

#

Ok so i was right about it being 111.11%

devout summit
#

Yep

shut parcel
#

What sum of money decreased by 89% will amount to $235?

#

I got an answer of $2,136.36

alpine sable
#

x-.89x=235

wary stream
shut parcel
#

Bc this server was in used

devout summit
#

Decreased by 89% means 11% remains

shut parcel
#

Yes

#

But its asking the sum of money

devout summit
#

Let the sum of money be x.
Then, x(11/100)=235

alpine sable
#

.11x=235

hard ether
#

how do you do this

shut parcel
#

I’m confused now

quiet forum
#

euclid can u ans my calculas's question?

shut parcel
#

So the answer is $21.36

queen mural
#

can somen plz help

#

in descrete sturcuters

glass lichen
#

discrete structures

#

but yeah... on what question?

queen mural
#

the 2nd one

#

Let d be the set of finite functions

glass lichen
#

T(15)?

#

oh 2nd question

#

yeah what about it?

queen mural
#

idk how

#

i dont understand what its asking

glass lichen
#

it wants you to plug in some integers into T

#

and get the set from D

queen mural
#

can we meet in math vc?

glass lichen
#

no

queen mural
#

how would i write it?

glass lichen
#

for example, $T(p)={1,p}$ for any prime p

ocean sealBOT
robust geode
queen mural
#

T(1)=(1)n?

robust geode
#

Be really careful about how the function is defined

#

You insert an integer

glass lichen
#

the output is a set

robust geode
#

And you get a result in D

#

And D is a set of sets

glass lichen
#

what are the positive divisors of 1?

queen mural
#

1

cursive cobalt
#

Which of the following is true? Select all that apply.
(A) If a number has only even powers in its prime factorisation, then it is a square.
(B) If an integer n has an odd number of factors, then n is a square number.
(C) If a number has only multiples of 3 in its prime factorisation, then it is a cube.
(D) If a number has n factors, and n is a multiple of three, then the number is a cube.

glass lichen
#

so what's the set that contains 1 and only 1?

robust geode
#

Remember, just like {{0, 1}, {1,2,3},...}

#

A set of sets

glass lichen
#

positive integers

cursive cobalt
queen mural
#

1?

glass lichen
#

The channel is in use

#

1 is not a set

queen mural
#

im so sorry im a visual learner this is killing me

glass lichen
#

sets need proper notation

robust geode
slate kayak
#

I tried forming an equation of a plane but it doesnt work

robust geode
#

In this case, a finite set

queen mural
devout summit
#

Set of divisors of n\\=$\left{d\in \mathbb{Z}^+\mid n/d\in \mathbb{Z}^+\right}$

robust geode
#

Then since D (the set of things that the application T returns)

ocean sealBOT
#

Euclid31415

glass lichen
#

I wouldn't worry about the explicit formula

#

@devout summit

devout summit
#

Ok yeah it can be written in elements...

robust geode
#

Since D is from the definition of the application T, a list of integers in which the number x in T(x) is divisible by

glass lichen
#

Nah, just the concept of it is sufficient

robust geode
#

Then the result of your application is simply a set

#

And in this case, regarding the results of T, a set of all the positive integers that your integer can be divided by

#

D is just a name used arbitrarly, it could be B or F or whatever

#

It's not an official name

#

Just to be clear

#

Maybe explaining it in vc might be better for you

keen sandal
#

Can someone please offer me some advice for this problem? I honestly have no idea where to start...

cursive cobalt
#

Which of the following is true? Select all that apply.
(A) If a number has only even powers in its prime factorisation, then it is a square.
(B) If an integer n has an odd number of factors, then n is a square number.
(C) If a number has only multiples of 3 in its prime factorisation, then it is a cube.
(D) If a number has n factors, and n is a multiple of three, then the number is a cube.

#

I am confused

#

nvm got it

slate kayak
#

The following points lie in one plane:
A (a,0,0)
B (0,2a,0)
C (0,0,a+1)
D (2,-1,2). Where (a ≠ 0)

What’s the value of a?

civic jungle
#

This sounds like a problem solving question

devout summit
#

If you do then, $(\overrightarrow{AB}\times \overrightarrow{AC})\cdot \overrightarrow{AD}=0$ ensures the condition.

slate kayak
#

Yeah i know vectors

#

Oh

#

I didn’t know that formula

ocean sealBOT
#

Euclid31415

slate kayak
#

I didnt know that formula existed so thanks

civic jungle
#

That's just a gimmick for the 3x3 determinant of the matrix formed by AB, AC, and AD

#

If you write the computation out

slate kayak
#

Ohh

devout summit
#

Exactly. Scalar triple product

slate kayak
#

Ok i’ll do that and see if it works

amber frigate
#

can someone help rq

#

pls

slate kayak
#

@devout summit Srry for ping but I get a = 0 v a = 2 but in my book it says the answer is a = -0.5 v a = 3

#

Should i send a pic of my work ?

devout summit
slate kayak
#

@devout summit here ^

devout summit
#

That is supposed to be cross product inside parentheses

slate kayak
#

Oh

#

Okay

harsh belfry
#

Hey is this channel still being used?

slate kayak
#

No

harsh belfry
#

Thanks

#

I've been looking at this for while and I have a true statement
However upon adding +1 to the left side of the equation I'm not sure how to make the right side true

slate kayak
#

Np

cursive cobalt
#

How many factors of 2520 are even?

#

I got 36

harsh belfry
#

In this instance I was unsure how to make the statement true.

#

What happens to the one?

#

Would appreciate any insight.

devout summit
harsh belfry
#

I was wondering if the 1/4 is technically still being divided by 1 would the equation look like this

#

o

cursive cobalt
#

Sorry to interrupt, but
How many factors of 2520 are even?

harsh belfry
harsh belfry
cursive cobalt
devout summit
#

$\frac{\frac{1}{4}}{\frac{x^2}{16}+1}= \frac{\frac{1}{4}}{\frac{x^2+16}{16}}=\frac{1}{4}\cdot\frac{16}{x^2+16}$

ocean sealBOT
#

Euclid31415

cursive cobalt
#

can I be a helper?

harsh belfry
#

oh so you added the one to make this simpler

#

I see

#

wow that explains alot

#

oh man this was so simple

mellow tinsel
#

I'm trying to find the determinant of an identity matrix subtracted by an n*n matrix.
Does this make sense?
|In-A|=|In|+|-A|

devout summit
scarlet heath
#

is the channel free rn?

mellow tinsel
devout summit
mellow tinsel
devout summit
mellow tinsel
#

I don't think A invertible in this case.

I'm given that A^21=0n.

worn prawn
#

X^2+bxy+cy^2 anyone know how to solve this problem with this equation >.<

pearl solar
#

there's no equation to solve there

sick scaffold
#

so, how would I use the log quotient property where loga-logb= log(a/b) when there are 3 values, so for example loga-logb-logc

wary jungle
#

can someone help me find dy/dx

#

<@&286206848099549185>

wary stream
wary jungle
wary stream
#

You use the quotient rule to find the derivative

wary jungle
#

my answer isnt one of the options

wary stream
#

Then you probably did it wrong

wary jungle
#

-2x(x-3)/3(-2x+3)^2 is what i got

#

are you able to get one of the options

worn prawn
harsh belfry
#

Should I post my question elsewhere? 😅

wary jungle
#

probably

wary jungle
#

except positive

#

so i did something wrong still

worn prawn
#

Need help with this as well v.v

wary jungle
#

whats the question asking for here

wary stream
worn prawn
wary jungle
#

can you explain the steps

#

other than saying do the quotient rule

#

like the process

wary stream
#

What do you get when you do quotient rule?

wary jungle
#

man idk

wary stream
#

What is quotient rule?

#

The formula

wary jungle
wary stream
#

So apply it

wary jungle
#

how

#

what is the process

wary stream
#

You have the formula, just apply it to the question you were given

wary jungle
#

how

wary stream
#

What's g(x) times f'(x)?

worn prawn
#

I'm lost rn was that for me

wary stream
worn prawn
#

Okie

mortal mantle
#

how do i know weather to integreate with respect to x or y

clever folio
#

Sometimes it doesn't matter and both are ez or hard.

mortal mantle
#

i think you should find 2 points that intersect right?

#

and then make them your bounds

clever folio
#

I'm pretty sure they do intersect at two points.

#

Are you making an error while graphing?

mortal mantle
#

oh im supposed to do this without the graph

clever folio
#

Try y=7 and -7

mortal mantle
#

wait both factor into the same thign

#

x-7 and x+7

clever folio
#

My point is they intersect at (0,7),(0,-7)

mortal mantle
#

yeah i understand that

#

idk how i didnt think of that

clever folio
#

You can solve it algebraically for the intersection by noting 49-y^2 = x = y^2 - 49 I think.

mortal mantle
#

yeah i tried that but maybe i just did the math wrong

#

since it only gave one intersect

clever folio
#

Then solve for y so 2y^2 = 2(49) hence y^2 = 49 so y = 7 or -7.

#

Did you take both the positive and negative square root?

mortal mantle
#

but i got the answer

#

i was just being dumb

#

i got one more if you are able to help

wanton spoke
#

To help out a classmate in need, the students of 9 Strontium decided to send a cash aid of $2 000. The students shared the cost equally. At the last minute, 10 students from the SSG chipped in, lowering the contribution per person by $10 for each student. How many students are there in 9-Strontium?
In this solution, why are we subtracting the new cost equation from the original cost equation? Why should we not just solve for n in the new cost equation?

clever folio
mortal mantle
#

its this one

#

i stuggled with this on my exam as well this same sort of concept

#

im just not sure how to approach it to begin with

#

so any guidance would be appreciated if you can

clever folio
#

Could it be integration by parts?

#

It's either that or u sub I bet.

#

This channel is occupied.

mortal mantle
#

its something about isolating the integral

#

but im not too sure

sacred ledge
#

hello

clever folio
sacred ledge
#

I need help to find the formula for this question

#

Over a short interval near time t = 0 the coordinate of an automobile in meters is given by x(t) = 27t − 4.0t3, where t is in seconds. At the end of 1.0 s the acceleration of the auto is -24 m/s2

#

just the formula please, thank you

mortal mantle
clever folio
#

Yeah I'm def still thinking it's ibp

#

Since you have g'(x) in ur integrand let dv=g'(x)dx and let u=x

#

Pretty sure when you work the ibp out you get the integral of xg'(x) on the lhs and on the rhs something you can evaluate using your given formulas

mortal mantle
#

so waht would our dv and u values be in this case

#

if we do ibp

clever folio
#

dv=g'(x)dx and u=x so v=g(x) and du=dx.

mortal mantle
#

hmm let me try it

mortal mantle
#

i think i might leave it for todayt

#

and come back to it another day

clever folio
#

What expression do you get after ibp?

mortal mantle
#

whe n i did everything it was -5x^2+c

#

i think my brain is just done rn lolol

clever folio
#

Hmm so I get $xg(x)-\int g(x) \dd{x}$.

ocean sealBOT
#

DootDooter

thorn kindle
#

Ok.

clever folio
#

There's a formula that lets you do the difference on that xg(x) bit and to use the definite integral.

#

It's just another version of ibp

#

So that seems like it gives you everything you need to get a constant on the rhs?

mortal mantle
#

rhs?

clever folio
#

The left hand side was just the xg'(x) integral.

mortal mantle
#

ah kk

clever folio
#

Here is the version of ibp i'm talking about btw

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If you use the substitutions I mentioned you can compute the whole rhs from your given info.

mortal mantle
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yeah taht makes sense

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i got it from here

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thank you for the help bro