#help-27

1 messages · Page 300 of 1

finite gale
#

2

#

And 5

#

<@&286206848099549185>

devout snowBOT
#

@finite gale Has your question been resolved?

latent quarry
latent quarry
#

The question can be solved immediately

latent quarry
#

Then the angle NMJ = 90-x

finite gale
#

im sorry im not understanding

latent quarry
#

What is the total amount of angle in a triangle

latent quarry
#

Then explain what is similarity in geometry

#

This is the 2 material we are going to use to solve this question

finite gale
latent quarry
#

Simmiliarity is when the shape have same angle but one is the enlargement of other

#

The similarity test in a triangle is if 2 triangles have 2 same angles then they are similar

latent quarry
latent quarry
#

JMN = 90-x right

#

But JML is 90

#

So angle NML = ?

finite gale
#

90-x i think?

#

Or wait

#

Hold up

#

Its 90-JMN angle?

latent quarry
#

LMN = X, MNL = 90, we already prove that our triangle is similiar

#

Do you understand about similarity or should I explain it

#

@finite gale

finite gale
finite gale
latent quarry
#

Remember the smaller triangle have base of 8 cm

#

While the larger triangle have base length of 15

#

Remember similiar triangle is just a enlargement of the same triangle

#

So

#

8*x = 15

#

Find x and now multiply 15*x and add it by 8 that is the answer

#

Draw it on paper to help you visualize it better

#

Make same triangle

#

One with base 8 and another with base 15

#

Remember the smaller triangle can be enlarged to the larger triangle by a scale factor

#

The scale factor is 15/8

latent quarry
devout snowBOT
#

@finite gale Has your question been resolved?

#
Channel closed

Closed by @finite gale

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

vestal bay
#

ABC is an inscribed triangle in a circle with point O as the center. From point D on the arc BC, the angles perpendicular to the lines BC, AC, and AB are dropped at E, F, and G respectively.
a. Prove that quadrilateral DEFC is a cyclic quadrilateral.
b. Prove that E, F, and G are on a straight line.

Could someone show me how to draw this figure? (Sorry if the problem sounds a bit off, I translated it from my native language.)

devout snowBOT
#

@vestal bay Has your question been resolved?

devout snowBOT
#

@vestal bay Has your question been resolved?

devout snowBOT
#

@vestal bay Has your question been resolved?

vestal bay
#

<@&286206848099549185> anyone?

valid silo
#

for a. notice the angle DEC and DFC

#

for b.

#

3 points are on a line if their angle is 180

#

try using angle chase, and the fact that DEFC and DEGB are cylic

#

you are done if you show CEF = BEG

vestal bay
#

I don't know how to draw the figure

vestal bay
valid silo
#

draw a circle

#

and take 4 points on it in order ABDC

#

make lines

#

AB

#

AC

#

and

#

BC

#

then make perpendicular lines from D onto AB, AC, and BC, and that is the diagram

vestal bay
valid silo
#

you can, if you make lines

#

not line segments

strange arch
#

not sure why nubudy provided a sketch :c

vestal bay
#

thankkss

strange arch
#

are the proof layouts themselves kind of clear?

strange arch
vestal bay
strange arch
#

which property do DEC and DFC share that implies that DEFC is cyclic

strange arch
#

yoppa

vestal bay
strange arch
#

I used the state-of-the-art professional-approved widely in the industry used software ms paint

vestal bay
strange arch
#

I mean it looks fairly cyclic

vestal bay
#

Oh we are supposed to draw extra circles?

strange arch
#

those are the circles

#

a cyclic quadrilateral is a quadrilateral with all of its points on a circle

#

so I drew the circles since you meant DFBG and DEFC don't look cyclic

#

regardless, for a) note that for any cyclic quadrilateral

#

DEC + DFC = 180° must hold

#

and since DEC is right-angled (perpendicular lines), DEC = 90°

#

and also DFC = 90°

#

thereby DEC + DFC = 180° is true

#

thereby DEFC is a cyclic quadrilateral

vestal bay
strange arch
#

and for b) I'd use the advice shreyanjha mentioned

strange arch
#

usually the main way to classify a cyclic quadrilateral

vestal bay
strange arch
#

A+B = 180°

#

C+D = 180°

vestal bay
strange arch
#

otherwise how would you know if a quadr. is cyclic

vestal bay
strange arch
vestal bay
strange arch
strange arch
#

you have two right angles at the upper points

#

which lie on the semicircle defined by the line at the bottom

#

implying all four points lie on the circle described by the semicircle

#

it essentially directly tells you DEFC is cyclic

vestal bay
#

Ohh okayy

#

I still don't really understand where does the DEC + DFC =180⁰ come from

devout snowBOT
#

@vestal bay Has your question been resolved?

vestal bay
#

@strange arch could you help abit more?

devout snowBOT
#

@vestal bay Has your question been resolved?

devout snowBOT
#

@vestal bay Has your question been resolved?

paper surge
paper surge
vestal bay
paper surge
#

idk, i'm just anwsering your question

devout snowBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

still rover
devout snowBOT
still rover
#

No idea how to go about solving this problem

frosty mantle
#

are you familiar with how to calculate the result of a definite integral if you have the function written out

still rover
#

that's the fundamental theorem right?

frosty mantle
#

yes

#

let me get an image for simplicity here

frail hull
#

hi guys i m new to this server

frosty mantle
frosty mantle
frosty mantle
frail hull
frosty mantle
#

you’re asked to solve the form on the left

#

and you’re given values for the form on the right

#

are you familiar with the form of an indefinite antiderivative

still rover
#

yes

frosty mantle
#

you always add a constant +c

#

but that constant +c can be anything

#

so theres multiple forms of the antiderivative

#

but they only differ in the +c constant

frosty mantle
# still rover

so at x=6 you’re given the values for both F(6) and G(6)

#

you can calculate the difference in the +C

#

and from there you can find the values of all F(x) from 1 to 6

#

and then you can apply the fundamental theorem

still rover
#

ohh ok

#

so F(5) would be 14?

#

am i going about this correctly

sterile geyser
#

correct

still rover
#

ok ty

#

.close

devout snowBOT
#
Channel closed

Closed by @still rover

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

topaz scaffold
#

A radio tower has a broadcast that can be heard in a circular area with a radius of 40 miles.
Suppose that you are driving along a straight road beginning 45 miles north of the radio tower
and ending 50 miles east of the radio tower.
Consider the radio tower to be at the origin of the Cartesian plane, i.e. the point (0,0).

(a) What is the equation of the circle that the radio broadcast can reach?

$x^2 + y^2 = 1600$

(b) What is the equation of the line the car is driving along?

$y=-\frac{9}{10}+45$

(c) What are the two points where the line intersects the circle?

$x^2+(-\frac{9}{10}+45)^2=1600$

what do I do after this?

woven radishBOT
#

227466

tall knoll
#

firstly, where do these two different fractions come from

devout snowBOT
#

@topaz scaffold Has your question been resolved?

devout snowBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

topaz scaffold
#

so then you insert it into x^2 + y^2 = 1600 as the y^2

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

lime wagon
#

how to integrate this 💀

devout snowBOT
topaz scaffold
#

eh

#

what happened to my question bro

lime wagon
trail eagle
#

Just u sub 16-8x

lime wagon
strange arch
#

if you insert the substitution into your integral it becomes easy to solve

lime wagon
#

damn

#

sheesh

strange arch
#

just determine the integration values

#

and sub

lime wagon
#

yes

#

done

#

thanks a lot

#

damn

#

it wasnt that hard, i was makin it hard in mah head 😭

lime wagon
#

.close

devout snowBOT
#
Channel closed

Closed by @lime wagon

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

devout snowBOT
#
Channel closed

Channel closed due to the original message being deleted.
If you did not intend to do this, please open a new help channel,
as this action is irreversible, and this channel may abruptly lock.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

dull thunder
#

how are we using logistic equations to solve this problem...?

dull thunder
#

i don't understand the 2nd and 3rd one...

final drift
#

so part 2 is asking when the maximum of $\frac{\mathrm{d}M}{\mathrm{d}t}$ is right?

woven radishBOT
#

Arnavutköy

dull thunder
final drift
#

so the maximum of $\frac{\mathrm{d}M}{\mathrm{d}t}$ will happen when $\frac{\mathrm{d}^2M}{\mathrm{d}t^2}=0$ right?

woven radishBOT
#

Arnavutköy

dull thunder
dull thunder
final drift
dull thunder
final drift
#

and solve for M

dull thunder
#

ohh i get the answer 150

#

what about 3rd one?

final drift
#

okay so you agree that one is correct right?

dull thunder
final drift
woven radishBOT
#

Arnavutköy

dull thunder
#

yes

devout snowBOT
#

@dull thunder Has your question been resolved?

devout snowBOT
#

@dull thunder Has your question been resolved?

dull thunder
#

.close

devout snowBOT
#
Channel closed

Closed by @dull thunder

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

dense scroll
#

Maybe a dumb question but I was trying to figure out how to calculate the volume of a solid made by rotating a curve around the x axis (like Gabriel's horn) and what I thought of was first expressing the area under the 2d curve with an integral from 0 to infinite or whatever to infinity, then integrating that times the area of an arc of a circle dθ from 0 to 2pi but it doesn't work,

And I found out a common standard method is integrating the volume of a disk with radius f(x) from 0 to infinity over

It seems like the methods are pretty much equivalent but turns out I'm wrong;

Could someone explain why my method is wrong?

tall cypress
#

find the volume of gabriel's horn by rotating volume of solid?

violet wind
#

"integrating that times the area of an arc of a circle dθ"

#

what?

dense scroll
#

no I meant like
I tried to derive on my own a method to calculate the volume of a solid constructed by rotating a curve

dense scroll
# violet wind what?

I'll try to explain myself better
Find the area under the 2d curve by integrating from 0 to infinity, then multiply that by slices of a circle

tall cypress
#

you wanna make sure that the integral of that curve from 0 to infinity converges

dense scroll
#

True

tall cypress
#

but have you heard about volume by rotation about x axis

dense scroll
#

Maybe assume the function is just defined between 2 finite bounds
So like from 1 to 5

dense scroll
#

Like the standard method for calculating its volume?

tall cypress
#

the formula is $\pi \int_{a}^{b} (f(x))^2 dx$

woven radishBOT
#

Slender

dense scroll
#

Yeah but I wanted to derive it on my own

#

I'm trying to figure out what's wrong with what I did because it seems like it's the same thing but in different ways

tall cypress
dense scroll
#

Calculate the area of a disk and integrate over the x axis or calculate the area of a slice and integrate over theta

dense scroll
tall cypress
dense scroll
#

I'm not looking for practicality I just wanted to do it myself and I made something that in my head should work but doesnt

tall cypress
#

double integral comes when you try to do in terms of polar coordinates

dense scroll
#

How would you calculate that

tall cypress
#

sure

#

so you wanna sum up all slices

#

to calculate the volume

dense scroll
#

Yeah

#

I think my error is in the way I calculate the slices

tall cypress
#

Gabriel's horn is generated by rotating 1/x graph

dense scroll
#

Yeah

tall cypress
dense scroll
#

Standard way is calculating a cross sectional disk and integrating over the x axis yeah

#

I wanted to do it another way, calculating a slice instead of a disk

#

Do you see what I mean or not

tall cypress
#

Something like this?

dense scroll
#

Yeah I guess

tall cypress
#

Yeah so basically

#

You want to find the area of that slice

#

Since that slice is "rotated"

#

It forms a circle

dense scroll
#

Yeag

tall cypress
#

but the radius is variable and changing

dense scroll
#

Yup

tall cypress
#

so let the radius function be R(x)

dense scroll
#

Ok

tall cypress
#

now your area of cross section is pi * R(x)^2

#

Makes sense?

#

Each slice is of size pi * R(x)^2

dense scroll
#

Wait but that's just the standard way

tall cypress
#

Yup thats how it is

dense scroll
#

Ok so it's not what I meant

tall cypress
#

You essentially slice

dense scroll
#

Guh

#

I don't mean slice across the x axis

tall cypress
dense scroll
#

Like the standard way cuts cuts that are parallel to the xz plane

#

Right

tall cypress
#

You want to look into 2d integration

#

using polar coordinates

dense scroll
#

I guess that's what I need

#

.close

devout snowBOT
#
Channel closed

Closed by @dense scroll

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

frozen aurora
devout snowBOT
frozen aurora
#

why is f true?

#

|u(t)| is a scalar function

#

but the result is a vector

thin inlet
#

is it?

#
  • denotes dot product
#

so u(t) dot u'(t) is a scalar function

#

@frozen aurora

ancient sluice
#

|a| = (a•a)/|a|

ancient sluice
frozen aurora
#

yep i missed that

thin inlet
#

its just because * is in front

frozen aurora
#

thanks

#

.close

devout snowBOT
#
Channel closed

Closed by @frozen aurora

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

viral lynx
devout snowBOT
viral lynx
#

I think this is not the way they want me to solve it, but is there a way to do this by turning it into arctan?

#

If you put the 3 to the left of the integration symbol it becomes 1/(x^2 - 16)

#

Which is pretty close to 1/(x^2 + 1)

#

But im just wondering about that negative sign, cause I cant put that inside a square root

#

Like if it was 1/(x^2 + 16) I could easily turn it into arctan(x/sqrt(16))/sqrt(16)

#

Like this^^

violet pine
#

i think this is more of a integration by partial fractions

#

do you know how that works

viral lynx
feral agate
#

you can write this as $$\frac1{\sqrt{-16}}\arctan\left(\frac{x}{\sqrt{-16}}\right)$$

viral lynx
#

Im just curious hehe

woven radishBOT
#

kheerii

viral lynx
feral agate
#

sure

viral lynx
#

Cause the negatives are inside the square root

feral agate
#

but it's not a very nice form to use

feral agate
violet pine
#

if that does not work then it is partial fractions

winter torrent
#

i would not recommend that approach lol

violet pine
#

this problem is mostly suggesting to use partial fractions

viral lynx
#

So I guess the answer is yes but dont

violet pine
#

alr

winter torrent
#

you can, and you can do the opposite (using partial fractions for 1 / (x^2 + 1) ) but it gets very messy

viral lynx
#

Well that answers my question, thank you everyone!!

#

❤️

#

.close

devout snowBOT
#
Channel closed

Closed by @viral lynx

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

lone stirrup
#

The pyramid ABCT has a triangular base where AB = 6 4. cm, AC = 5 8. cm
and ∠A = 45°. The side edge AT is 7.4 cm long and forms the angle with 60° with
the ground surface.
a) Find the area of ​​the base.

My first approach was to use the area formula

1/2 * h * b * sin(v)

But that resulted into 1/2 * 5.8 * 6.4 * sin(45) = 13.12cm^2

Why cant I use the area formula here?

rigid sandal
#

anyone who wrote amc8 today?

devout snowBOT
#

@lone stirrup Has your question been resolved?

devout snowBOT
#

@lone stirrup Has your question been resolved?

devout snowBOT
#

@lone stirrup Has your question been resolved?

devout snowBOT
#

@lone stirrup Has your question been resolved?

marsh osprey
#

it is the perpendicular distance from the point above

#

oh you did that

devout snowBOT
#

@lone stirrup Has your question been resolved?

devout snowBOT
#
Channel closed

Closed by @lone stirrup

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

dire osprey
#

Hi, I am struggling to understand this unit as a whole but especially how to decide whether a value will be less than and equal to, less than, etc than x/y! For example, why is x greater than/equal to -3 in this ss? I sorta forgot to restudy this unit before my final tomorrow and am freaking out a bit hahaha. Thank you!

dire osprey
#

I'm looking 😭

#

i have been i promise

#

i just dont understand

smoky nimbus
#

Observe the function, notice how the function starts at the left then goes right, meaning x values are getting larger, larger than -3

dire osprey
#

I think im still lost. i wrote {x|-2>- x >-4

gleaming socket
#

Correct

gleaming socket
#

Do the y axis too

dire osprey
smoky nimbus
#

It's an closed circle at x = 4

#

So it's equal to

dire osprey
#

omg the points decide that??

smoky nimbus
#

Yes

dire osprey
#

i thought they just decided between the brackets when writing coords

#

i see

#

'thank you

smoky nimbus
wind mason
#

especially for the y-values

dire osprey
#

thanks for the help guys i think im just not cut out to get this lol i dunno

#

.close

devout snowBOT
#
Channel closed

Closed by @dire osprey

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

gray axle
#

Translation for Ex 9
Idk what to do here, idk whhat to do even in "1-"

strange arch
#

@gray axle

#

from here try to simplify as much as possible

#

crunch everything into the ground

gray axle
#

Ty, I will open new ticket If something else is difficult for me

#

.close

devout snowBOT
#
Channel closed

Closed by @gray axle

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

finite gale
#

!status

devout snowBOT
#
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
devout snowBOT
finite gale
#

2

#

,rotate

woven radishBOT
gleaming socket
#

Show work

finite gale
#

i got like nothing done, i got so stuck

strange arch
finite gale
strange arch
#

so you can work with any value for the sidelength or totalarea

#

starting with totalarea=1 can be fairly intuitive

#

but you can also use sidelength = 1

#

if you know the side-length is 1

#

what's the area of the hexagon?

dark tundra
#

I see there are some lines in your hexagon

#

Perhaps you can try forming those little triangles all over the hexagon

finite gale
dark tundra
#

Sometimes the solution is much easier than you think

strange arch
#

so you can also perceive the hexagon's area as "6 * GreenTriangle"

#

but how many green triangles is the gray area?

finite gale
strange arch
#

how much a bit

finite gale
#

oh yes 1.5

#

i just saw it in my head

strange arch
#

kk

finite gale
strange arch
#

sure

finite gale
strange arch
#

1.5 / 6 green triangles

#

= 1/4

finite gale
#

oh damn that simple 🤦‍♂️

#

thx

#

.close

devout snowBOT
#
Channel closed

Closed by @finite gale

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

latent scaffold
#

can anyone help me with this?

devout snowBOT
latent scaffold
#

<@&286206848099549185>

formal ingot
latent scaffold
formal ingot
#

No, as in go through each option without submitting, for example, option 2

#

Option 2 says a rotation of the triangle by 90 degrees

#

But has the triangle being rotated?

latent scaffold
#

you mean like process of elimination

#

also sorry for late response

#

oh

#

I got the first option

#

as my answer

#

@formal ingot

formal ingot
#

Have you tried all the other options

latent scaffold
#

yup

#

so am I correct?

formal ingot
#

So preimage is a reflection, right?

latent scaffold
#

pretty sure

#

yup

formal ingot
#

So it wouldn't be 1

#

Cause it wasn't mirror in anyway

latent scaffold
#

oh yeee

#

your right

#

so it has to be the last one right?

#

It would be I think

#

but abc is like

#

the original

#

the ones that say A'B'C' were translated 8 units right and 3 units down

crisp mesa
formal ingot
#

But I think you get the point

latent scaffold
latent scaffold
#

bet bet

#

thanks guys

crisp mesa
#

No Problem.

latent scaffold
#

.close

devout snowBOT
#
Channel closed

Closed by @latent scaffold

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

violet trail
#

Hello

devout snowBOT
#

@violet trail Has your question been resolved?

devout snowBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

pine bay
devout snowBOT
pine bay
#

i need to solve B)

#

i followed the steps yet i got it wrong

toxic grove
#

What did you do?

pine bay
#

here u go

#

@toxic grove

#

brother

toxic grove
#

This absolutely isn't anywhere near my area so no promises

#

But your approximation of 1.066^(1/12) of 1.0055 isn't accurate at all once you raise it to the power of 240

#

The error gets quite large

#

So that could be the problem

#

It also looks like you copied down the result of 2.7299/0.0055 wrong from your calculator (even though those numbers aren't correct in the first place)

#

Assuming your formulae are correct then that's what's probably gone wrong

pine bay
#

my formula was wrong

#

but @toxic grove

#

general question

#

when finding interest, we always subtract the Future Value or Present Value from our Total payments to get Interest?

toxic grove
#

Compound interest is always based on how big the debt is at that moment

pine bay
#

okay

#

so

toxic grove
#

when you say Interest, do you mean how much was charged in total?

#

Because that's just total payments minus the initial value

#

I've actually solved it now so I'm not totally clueless anymore

#

But I'm not an expert

pine bay
#

understood

#

ok so what i actually mean is

#

listen i got the right answer

#

and u get the R value, multiply it by 245280 which gives you the total payments, Subtract 136000 from that and u your interest correct?

#

@toxic grove

toxic grove
#

By R, do you mean how much he pays each month?

#

Because total payments would be that multiplied by 240

pine bay
#

R value is what were solving for

toxic grove
#

The answer to part a?

pine bay
#

R= Regular payment each compounding period

toxic grove
#

Okay yes, how much he pays each month

#

He pays it for 240 months, so the total payment is R * 240

#

But then yes, subtract 136000 from that and you get the total interest

#

That's how much extra paul ended up paying

pine bay
#

ok

#

great

#

now listen carefully

#

mb

#

@toxic grove

#

u still here

#

ok now listen carefully

toxic grove
#

Ye

pine bay
#

for 11b

#

this question right here

#

it says calculate the future value and INTEREST

#

correct?

toxic grove
#

Yes

pine bay
#

good

#

now

toxic grove
#

I assume you know what those mean?

pine bay
#

yes. now listen

#

when solving for interest. to get the right answer i had to subtract the total payment from the FV

toxic grove
#

Yes

pine bay
#

but in this question we just did, 15b i had to subtract PV from the total payment

toxic grove
#

Okay but in the debt example, it's pretty much the same thing but in reverse

#

You shouldn't think of interest as a formula like that

#

In the debt example, interest was how much extra he had to pay on top of the 136000

#

Because the bank kept charging interest

#

It is mathematically quite similar, but present value and future value are swapped

pine bay
#

alright so when its FV were subtracting the total payments FROM FV but when its PV were subtracting PV FROM the total payments?

toxic grove
#

Yes

#

It kind of feels backwards, but that's because in the debt example it was effectively you paying the interest, whereas in the annuity, the bank is paying the interest

#

It'll be much less confusing if you think of "interest" as an english term rather than a formula to be memorised

pine bay
#

i kind of understand because whenver its FV, The total payments is less than the FV

#

but when its PV the Total payments is MORE than PV

#

true?

toxic grove
#

Other things are flipped as well, because in the debt example, the future value is 0, but for the annuity example, the present value is 0

#

Yes

pine bay
#

understood

#

fully understood

#

im about to do this question now, last one on my exam review. tryna solve it too and we see if we got the same shit?

toxic grove
#

That's because in the debt example the bank were charging you interest (so it takes away from your payments), but in the annuity example they're paying you interest on top of your payments

pine bay
#

got it

toxic grove
#

Sure but again no promises, I'm no economist

pine bay
#

its descrete functions 😂

#

yo

#

@toxic grove it dont say how much money adams putting in the account per month

#

only ken

#

wtf

toxic grove
#

That's what you have to calculate

#

Ken puts in $100 per month and ends up with some amount of money by age 55

#

Adam puts in $x per month and ends up with the same amount

#

Solve for x

pine bay
#

gotchu

#

this is FV right

toxic grove
#

Yes

pine bay
#

im at

#

FV=R(5.6631)

#

oh wait

#

R is 100

#

im dumb

toxic grove
#

So you think FV = $566?

#

That doesn't soundn right

pine bay
#

no wait

#

i thin kits 556

toxic grove
#

If ken puts $100 into the account each month, then he would have at least that amount by month 6

#

Even without interest

pine bay
#

oh shit ur right

toxic grove
#

He pays into the account for 35 years, it's gotta be a lot more than 500 dollars

pine bay
#

whered i go wrong

#

i mean

#

i multiplied 35 by 12

#

and devided 0.054 by 12

#

does 556x420 sound right

toxic grove
#

Where did 556 come from?

pine bay
#

here bro

#

ill send a pic of my work

toxic grove
pine bay
#

look bro

#

i couldnt have gone wrong anywhere

toxic grove
#

Okay you're close

pine bay
#

what did i do wrong

toxic grove
#

But i is 0.0044 right?

#

You've got i = 1.0044

#

On the bottom of this fraction

pine bay
#

i forgot to subtract the 1 in the denominator

#

right

#

oh yeah

#

cus the its 1+i

#

so i is without the 1

toxic grove
#

Exactly

pine bay
#

124252.45

#

right

toxic grove
#

Yep approximately

pine bay
#

thats my FV

toxic grove
#

Yes

pine bay
#

ok so now we plug it in for FV into adams wuqation and solve for R

#

am i right

#

or am i right

toxic grove
#

Sounds right

pine bay
#

finally bro

#

yo

#

@toxic grove

#

here we go bro

#

istg i have to be right

#

is R = 227.727

toxic grove
#

It might be

#

Show me your working?

#

I got 281 but I used a lot more precision than you did

#

It does feel quite far off so I don't think it's right

pine bay
#

yeah

#

true

#

ok well

#

here

#

im right

#

i just typed it in the calculator

#

this equation equals R447.39

toxic grove
#

Alright a few problems

pine bay
#

wats up

toxic grove
#

Firstly, how many months in 18 years?

pine bay
#

dont even tell me

#

dont even tell me i reaed the calculator wrong

#

no fucking shot

#

its always somthing bro

#

its always somthing i swear

toxic grove
#

Hahaha it happens to all of us dw

pine bay
#

ok dats all tho right

toxic grove
#

Secondly

#

The 447 number is wrong because of the wrong number of months

pine bay
#

ok new answer; 282.34

toxic grove
#

But you did the division wrong as well

#

282 is much more like it

pine bay
#

1 problem bo

#

oh wait actually

#

i got it right on the exact decimal

#

282.34-100=182.34

#

so he had to pay 182 more dollars than his bro

#

and would u look at that

#

got it correct right down to the decimal

toxic grove
#

Yep wd

pine bay
#

ai bro

#

i wana sleep but i cant

#

cus yo

#

@toxic grove my boy

#

he got a hold of the exam and i was looking at it

#

1 question i dont get that much

#

some quadratics shit

#

pretty easy

#

i just forget what to do

toxic grove
#

What, the actual one you're practising for?

pine bay
#

nah nah just a old one

toxic grove
#

Okay

pine bay
#

ok so

#

a)

toxic grove
#

So what are you thinking?

pine bay
#

quick question first

#

what does the quadratic formula give me again

#

zeros?

toxic grove
#

Yes

pine bay
#

ok understood

toxic grove
#

If ax^2 + bx + c = 0, then the quadratic formula will give you the possible values for x

pine bay
#

the maximum no ??

#

that would give u the vertex which includes the max

toxic grove
#

Not necessarily

#

Wdym?

pine bay
#

making the equation = 0

#

gives u 2 brackets when u factor it

toxic grove
#

Yes

pine bay
#

and if u fill those in

toxic grove
#

So there are two possible solutions

pine bay
#

those are your zerios

toxic grove
#

Yes

pine bay
#

find the axis of symatry between those 2 numbers

#

and thats the max

#

y=max

#

no?

toxic grove
#

If you're trying to solve for the maximum height of the balloon then yeah that's one way of doing it

pine bay
#

got it

toxic grove
#

Part (a) asks for how long it spends in the air though

pine bay
#

and those 2 numbers that i found the axis of syetry of, 1 is probably gonna be negative and ones probably gonna be positive right?

toxic grove
#

It should be yes

pine bay
#

i use the positive one and thats my x axis

toxic grove
#

Wdym

pine bay
#

ok im confusing my self

#

forget all that

#

ok a) how long was the balloon in the air

toxic grove
#

Yeah the positive one is the only "real" solution, the negative one is there just for mathematical reasons

pine bay
#

true

#

ok so

#

a) how long was the balloon in the air

#

what is it trying to ask me here

toxic grove
#

How much time passed between him throwing the balloon, and the balloon hitting the ground

pine bay
#

mm

#

alr

#

so

#

this is a parabola with a maximum cus its facing downwards

toxic grove
#

Yes

pine bay
#

now its getting confusing cus what do u mean in the air

#

that shit makes no sense

toxic grove
#

The balloon isn't gonna accellerate into the air so that makes sense

pine bay
#

yurrr

#

so

toxic grove
#

h(t) tells you the height of the balloon at time t right?

#

If h(t) > 0 then the balloon is in the air

pine bay
#

h(0)= and solve

#

am i right

toxic grove
#

No

pine bay
#

fuck

toxic grove
#

h(0) is just the height of the roof

#

h(t) = 0

#

solve for t

#

That's what you want to do

pine bay
#

im saying make t=0

#

oh

#

solve for t?

#

dont u do that by making the equation = 0

#

or can u use quadratic formula

toxic grove
#

Here's what's actually happening

#

The red circles are where h(t) = 0

#

But the solution in the past doesn't really exist, because the ball was thrown to the right

#

Yes, you make h(t) = 0

#

But not t = 0

#

You want to find the value of t

pine bay
#

holdup holdup holdup

#

so

#

quadratic formula gives me the zeros, but technically so does making h(t)=0

#

wat do i do

#

whic one

toxic grove
#

In theory h(t) has negative values as well but you can see they don't really mean anything

toxic grove
#

They're exactly the same

#

You set h(t) = 0

pine bay
#

which ones faster

toxic grove
#

Then use the quadratic formula to solve for t

pine bay
#

snm

toxic grove
#

If you know of some other way then you're welcome to use that instead

pine bay
#

nice bro u js got active role

#

big ups for u

toxic grove
#

Omg my name has color now

toxic grove
#

I don't like it I won't lie lol

#

It's a bad look for me

#

Too exciting

pine bay
#

just to be clear h(t)=0 will give me 2 brackets, i need to add a number into the brackets to make them = 0 and those numbers are my 0s right

toxic grove
#

Yes

pine bay
#

but quadratic formula will straight up give my zeroes

toxic grove
#

If you find that h(t) = (x - 5) (x + 3) for example, then the 0s are 5 and 3

pine bay
#

5 -3

#

are my zeroes

toxic grove
#

Yes sorry that's what I meant

pine bay
#

yeah yeah

#

but

#

quadratic

#

they would just give me 5 and 3

toxic grove
#

So either you can factorise it and then work out the 0s, or you can use the formula to get the 0s (and then factorise it if you wanted)

#

Yes

#

Bottom line is it doesn't matter

#

Do whatever

pine bay
#

say nm

#

im doing quadratic

#

brb gang

#

wait

#

before i go for a sec

#

i got a a quick question befores olving this

#

first: for discrimanent formula: if the x>1 = theres going to be 2 zeroes, if 0<x<1 theres going to be 1 zero, and if 0>x theres no zeroes

#

correct?

toxic grove
#

No

pine bay
#

wait what

#

for this formula

toxic grove
#

if x > 0 there are 2 zeroes, if x = 0 there is 1 zero, and if x < 0 then there are no zeroes

#

Yes

pine bay
#

OH yeah

#

shit mb

#

i remmeber now

toxic grove
#

It makes perfect sense if you look at the quadratic formula

#

You can't sqrt a netagive number

#

And if it's 0 then +-sqrt(that) are both going to be the same

pine bay
#

oh shit true

#

because ur adding nothing to both answers

toxic grove
#

So there are still technically two zeroes, just they have the same valune

#

Exactly

#

Well

#

Adding nothing to one of them, and subtracting nothing from the ohter

pine bay
#

basically the answers are going to stay the same and theya re the same

toxic grove
#

Yeah

pine bay
#

yeah yeah

#

ai ima solve

toxic grove
#

You don't need discriminant for this question though

pine bay
#

yeah ik

#

i was just wondering

#

yk what im also wondering

toxic grove
#

Go on

pine bay
#

ok found it

#

alr so

#

9y^2-4

I wrote this as (3y-2)^2 why is this wrong

toxic grove
#

Because that's not right

#

Expand (3y - 2)^2

#

You don't get 9y^2 - 4

pine bay
#

is itbecause the square root of -4 can be negative or positive so i ned to make it 3y-2 3y+2

toxic grove
#

positive 4, not negative

#

Negative 4 doesn't have a square root

#

But yes

#

2 and -2 are the two solutions to y^2 = 4

pine bay
#

ok

#

and

#

theres this other one

#

i forget what its called

#

its where theres an a b and c value

#

and u square root a and c

#

and use the sign of b

#

dyk what im talking ab

toxic grove
#

No

pine bay
#

ok for example

#

9y^2+12y+4

#

u squareroot 9y^2 and 4

#

and then u make it (3y+2)^2

#

u get what im saying

toxic grove
#

Oh are you talking about completing the square?

pine bay
#

no no no

#

not that bro

toxic grove
#

Well then idk what you're talking about

pine bay
#

wait maybe

#

but bro

toxic grove
#

Not saying you're wrong

pine bay
#

isnt completing the square

#

when u factor the first 2

#

numberes

toxic grove
#

Yeah

pine bay
#

then take b value divide it by 2, square it then add it and subtract it then take the factored number multiply it by the - one and bring it out of the bracket

toxic grove
#

Something like that yes

pine bay
#

ok look

#

9y^2 + 12y + 4

#

how would u solve this

#

like YOU

toxic grove
#

It's just another way of solving quadratics, you don't need to do it if you don't want to

#

I'd probably divide the whole thing through by 9, then complete the square

pine bay
#

oh?

#

but what was that thing that the middle number (b) /2 squared or smth has to equal the c value or smth

#

to use the rule

toxic grove
#

That's what I always used to do when I was at school

#

Yeah I still don't know what you're talkinga bout

#

If b^2 = 4ac then the discriminant is 0 and there is only one root?

#

That's all I can think of

pine bay
#

OH

#

PERFECT SQUARE TRINOMIAL

#

ring a bell?

toxic grove
#

No

pine bay
#

No?

#

perfect square trinomails

#

this

toxic grove
#

Oh so just (ax - b)^2 for some a?

toxic grove
#

I've not heard it called that before but yeah it's the same thing

pine bay
#

ok so for the middle number

#

middle number has to equal to the square roots of a and c times 2

toxic grove
#

if $b = 2\cdot \sqrt a \cdot \sqrt c$ then $b^2=4ac$

woven radishBOT
#

depression

pine bay
#

got it bro

#

love u

#

ima solve htat question now

#

the quadratic shit fam

#

yo

#

@toxic grove

#

im at a point where the 2 zeroes are -27-26/-9.8 and -27+26/9.8

#

do i solve the devision first

#

even tho the 2 numbers are in the numerator

toxic grove
#

Do whatever the formula tells you to do

#

Work out the top

#

Then the bottom

#

Then divide the top by the bototom

pine bay
#

ok

#

yeah i fucked up

#

i defenitely fucked up big time bro

toxic grove
#

Yeah I thought so

#

Neither of them looked right

#

That's okay

#

Try again

pine bay
#

whered i go wrong

toxic grove
#

Missed out a minus sign

#

/ added one in idk

pine bay
#

wait

#

its 72.9+47.04 right

toxic grove
#

What is?

pine bay
#

in the bracket

#

2nd equation i the ss u sent me

#

729+47.04

#

is what it should be

#

no?

toxic grove
pine bay
#

bet

toxic grove
#

But you did 729 plus 47.04

#

Sorry no

#

You did minus but it should be plus

pine bay
#

yea

#

nah i fucked up again

#

ok

#

i got -0.087 and 5.56

#

as my zeroes

#

ths shit actually makes no sense to me

#

how are my zeroes so discombobulated

toxic grove
#

Yeah that looks right

pine bay
#

ok bet

toxic grove
#

Why wouldn't they be?

pine bay
#

so

#

5.56 seconds is the answer to my first question

toxic grove
#

There's no reason it should have nice numbers

#

Yep

pine bay
#

how high off the ground was the balloon innitally thrown

#

now how tf do i know that

toxic grove
#

What do you think?

pine bay
#

i think we plug 5.56 into the equation

toxic grove
#

Try it

pine bay
#

for t

#

ok

#

125m?

toxic grove
#

No

pine bay
#

fuck

#

i was wrong then

toxic grove
#

Plugging in your answer to part a should give you 0

#

That's what you worked out

#

In part a

pine bay
#

why the fuck didnt it give me zero then

toxic grove
#

What did it give you? 125?

pine bay
#

yes

toxic grove
#

Then you typed it in wrong

#

If you got about 1 then it's because 5.56 isn't very accurate

#

But 125 means you typed it in wrong

pine bay
#

ok look

#

-4.9(5.56)^2 + 27(5.56) + 2.4

#

= -27.244+150.12+2.4

#

= 125.276

toxic grove
#

You didn't square 5.56

pine bay
#

i gnored the square

#

yup

#

nice

#

i always do smth bro

#

aint gon have an answer sheet on my exam

#

gon make so many silly mistakes

#

i got 1.04

toxic grove
#

Yeah

#

You typed it in right

#

But 5.56 isn't very accurate

#

The actual answer is 5.5977

pine bay
#

mmm ok

toxic grove
#

But you probably calculated it correctly

pine bay
#

would the answer be more accuriate if i just plugged 0 in cus that means the height when the ball was at 0m

toxic grove
#

And truncated the numbers on your page is my best guess, I wouldn't consider it a mistkae

#

Yes

#

That's the answer

pine bay
#

wait so plugging 0 in and 5.56 in is the same thing?