need help plz | Mathematics | Page 1

shut hawkBOT Oct 22, 2024, 2:22 AM

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foggy apex Oct 22, 2024, 2:26 AM

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First question tests product rule

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Second qn tests chain rule

elder birch Oct 22, 2024, 2:27 AM

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Hi thanks for replying

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um

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are the answers -10

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and -1 by any chance?

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i used the product rule for a

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and i multiplyrd the two functions

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which gave me -10

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and then for b i got -1

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used the chain rule

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is that right?

foggy apex Oct 22, 2024, 2:31 AM

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Can I see your workings for a.)

elder birch Oct 22, 2024, 2:33 AM

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i did

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u' (-2) =3

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multiplied (-3)

foggy apex Oct 22, 2024, 2:34 AM

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They’re asking for u’(-3)

elder birch Oct 22, 2024, 2:34 AM

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+1

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oohhhh

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so i did it wrong

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shoot

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im confused

foggy apex Oct 22, 2024, 2:35 AM

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So by product rule:
$u’(x)=f’(x)g(x)+f(x)g’(x)$

stable geyserBOT Oct 22, 2024, 2:35 AM

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denzio321

foggy apex Oct 22, 2024, 2:36 AM

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What is f’(-3)

elder birch Oct 22, 2024, 2:37 AM

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-7?

foggy apex Oct 22, 2024, 2:37 AM

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Use rise/run formula

elder birch Oct 22, 2024, 2:38 AM

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rise run formula

foggy apex Oct 22, 2024, 2:38 AM

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The gradient of a line formula

elder birch Oct 22, 2024, 2:38 AM

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okay

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so its not -7 right

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i did nt use rise run for that

foggy apex Oct 22, 2024, 2:39 AM

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Well in the first place the line is going upwards

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So it can’t even be a negative gradient

elder birch Oct 22, 2024, 2:41 AM

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idk

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im still confused

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so 1a) has to be positive okay

foggy apex Oct 22, 2024, 2:42 AM

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Think back to your early school days

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How do you find the gradient of a line

elder birch Oct 22, 2024, 2:43 AM

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y2-y1/x2-x1

foggy apex Oct 22, 2024, 2:45 AM

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Yes

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Use that

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So what’s the gradient

elder birch Oct 22, 2024, 2:50 AM

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2

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1a is 2 correct?

foggy apex Oct 22, 2024, 2:51 AM

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elder birch 1a is 2 correct?

What did you find f’(-3) to be first

elder birch Oct 22, 2024, 2:53 AM

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what do you mean

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sorry

foggy apex Oct 22, 2024, 2:53 AM

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What is the value of f’(-3)

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That you found using rise/run

elder birch Oct 22, 2024, 2:54 AM

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2?

foggy apex Oct 22, 2024, 2:54 AM

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No

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Which points did you use

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On the line

elder birch Oct 22, 2024, 2:54 AM

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oh i used 1- (-3) / -2 - (-4)

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which gave me 4/2

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=2

foggy apex Oct 22, 2024, 2:56 AM

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But those points aren’t on the line?

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Look more closely

elder birch Oct 22, 2024, 2:58 AM

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1

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is the only point on the line

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foggy apex Oct 22, 2024, 2:59 AM

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So you picked the points (-2,1) and (-4,-3) right

elder birch Oct 22, 2024, 3:00 AM

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i used 1-(-3)/-2-(-4)

foggy apex Oct 22, 2024, 3:01 AM

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elder birch

elder birch Oct 22, 2024, 3:01 AM

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but u said use thge ppoints only on the line

elder birch Oct 22, 2024, 3:01 AM

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foggy apex So you picked the points (-2,1) and (-4,-3) right

so it would have to be this what u said

foggy apex Oct 22, 2024, 3:01 AM

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foggy apex

The points u picked aren’t even on the line

foggy apex Oct 22, 2024, 3:03 AM

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elder birch

Using these points
$m=\frac{0-(-1)}{1-(-3)}=\frac{1}{4}$

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Try using these points drawn in black @elder birch

elder birch Oct 22, 2024, 4:05 AM

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hii sorrry

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my wifi went out

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im back

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im still confused

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i tried the points you gave me but

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idk

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like i got this question right

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but i cant get the graph question right

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i dont know if im overthinking it, or if i dont understand graphs

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lol

foggy apex Oct 22, 2024, 4:15 AM

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Using these points
$m=\frac{0-(-1)}{1-(-3)}=\frac{1}{4}$

stable geyserBOT Oct 22, 2024, 4:15 AM

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denzio321

foggy apex Oct 22, 2024, 4:15 AM

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foggy apex Using these points $m=\frac{0-(-1)}{1-(-3)}=\frac{1}{4}$

The points here

elder birch Oct 22, 2024, 4:18 AM

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ohhhh

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ive been doing it wrong

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im so dumb

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wow

foggy apex Oct 22, 2024, 4:18 AM

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Try for the g(x)

elder birch Oct 22, 2024, 4:18 AM

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okay

foggy apex Oct 22, 2024, 4:18 AM

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What's g'(-3)

elder birch Oct 22, 2024, 4:19 AM

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so f(x) is 1/4

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now i have to get g(x) right

foggy apex Oct 22, 2024, 4:19 AM

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f'(-3) is 1/4

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Now find g'(-3)

elder birch Oct 22, 2024, 4:21 AM

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g'(-3) should be -1/2

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correct?

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-4-(-3)/-2-(-4)

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=-1/2

foggy apex Oct 22, 2024, 4:22 AM

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Draw the points you used?

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Just wanna see what points you used

foggy apex Oct 22, 2024, 4:22 AM

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foggy apex Using these points $m=\frac{0-(-1)}{1-(-3)}=\frac{1}{4}$

Like this

elder birch Oct 22, 2024, 4:22 AM

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how do i draw?

foggy apex Oct 22, 2024, 4:23 AM

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Use remix

elder birch Oct 22, 2024, 4:23 AM

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i dont know how to do that sry

foggy apex Oct 22, 2024, 4:23 AM

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Just tell me the points you used

elder birch Oct 22, 2024, 4:23 AM

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okay

foggy apex Oct 22, 2024, 4:23 AM

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In (x, y) form

elder birch Oct 22, 2024, 4:24 AM

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(-4,-3) (-2,-4)

foggy apex Oct 22, 2024, 4:25 AM

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So these points?

elder birch Oct 22, 2024, 4:25 AM

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yeah

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is that wrong

foggy apex Oct 22, 2024, 4:26 AM

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foggy apex

Are those points on the line?

elder birch Oct 22, 2024, 4:27 AM

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ooh

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nevr mind

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it shoudl be (-2,-2) and (-3,1)

foggy apex Oct 22, 2024, 4:27 AM

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Yeps

elder birch Oct 22, 2024, 4:27 AM

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ah

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now i do the same thing

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rise/run

foggy apex Oct 22, 2024, 4:28 AM

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Yes

elder birch Oct 22, 2024, 4:28 AM

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okay okay makes sense

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should be 3 correct?

foggy apex Oct 22, 2024, 4:32 AM

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-3

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Close enough

elder birch Oct 22, 2024, 4:32 AM

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ohh never

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mind

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3/-1

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-3

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ur right

foggy apex Oct 22, 2024, 4:33 AM

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stable geyser **denzio321**

So now just find u'(-3)

elder birch Oct 22, 2024, 4:33 AM

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ok with 1/4 and -3

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-15/4?

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u'(-3) = -15/4

foggy apex Oct 22, 2024, 4:39 AM

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How'd you work that out?

elder birch Oct 22, 2024, 4:40 AM

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i did u'(-3) =f'(-3)

foggy apex Oct 22, 2024, 4:41 AM

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What

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Why

elder birch Oct 22, 2024, 4:42 AM

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stable geyser **denzio321**

i used the formula u gave me

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u'(-3)

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and f'(-3)

foggy apex Oct 22, 2024, 4:43 AM

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elder birch i did u'(-3) =f'(-3)

No the formula says
u'(x) =f'(x)g(x) +f(x) g'(x)

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Where are you getting
u'(-3)=f'(-3) from

elder birch Oct 22, 2024, 4:44 AM

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omg

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i get it now

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wait so what would g(x) and f(x) be

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if f'(x) is 1/4

foggy apex Oct 22, 2024, 4:47 AM

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elder birch wait so what would g(x) and f(x) be

Use the graph cuh

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What's f(-3)

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I'm not talking about f'(-3),that's the derivative

elder birch Oct 22, 2024, 4:48 AM

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-1?

foggy apex Oct 22, 2024, 4:48 AM

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Mhm

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Then g(-3)?

elder birch Oct 22, 2024, 4:48 AM

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1

foggy apex Oct 22, 2024, 4:49 AM

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Yep so what is u'(-3)

elder birch Oct 22, 2024, 4:50 AM

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13/4

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finally

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that should be correct right

foggy apex Oct 22, 2024, 4:53 AM

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Yes

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Finally

elder birch Oct 22, 2024, 4:53 AM

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finallyyy lol

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sorry for bothering you i was just confused now i understand thanks

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so the answers for 1a is 13/4, now how would i go about solving b

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would i do the same thing

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just instead of -3

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this time 4?

foggy apex Oct 22, 2024, 4:55 AM

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Nah maybe someone else can help

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<@&286206848099549185>

elder birch Oct 22, 2024, 4:55 AM

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okay

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should i just close this chat?

foggy apex Oct 22, 2024, 4:56 AM

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Just wait

#need help plz