#help-39

1 messages · Page 180 of 1

plush dagger
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Feel free to ask questions

stoic imp
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you didnt show how you got the orthogonal complement of T

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nor the orthogonal complement of S

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we can compute it together

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let v =(x1,x2,x3,x4)

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T = <(-1,1,0,0),(4,0,1,1)>

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v . (-1,1,0,0) = 0

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i) -x1+x2 = 0

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ii) 4x1+x3+x4=0

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i) -x1+x2 = 0 <==> x1 = x2

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ii) 4x1+x3+x4=0 <==> x3 = -x4 -4x1

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(x1,x2,x3,x4) = (x2,x2,-x4-4x2,x4)

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T orthogonal is = <(1,1,-4,0),(0,0,-1,1)>

plush dagger
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Yep

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Looks good

stoic imp
# plush dagger

you prolly did a mistake when finding the orthogonal complement of T because the dimension of T orthogonal + T should give the whole space R^4

plush dagger
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Hmm hold up

stoic imp
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dim(T)+dim(T perp) = dim(R^4)

plush dagger
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Yep

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I did

stoic imp
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since T and T perp are complementary subspaces and both are subspaces of R^4 their dimensions should sum up to R^4

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Also you didn't show how you got that basis for S

plush dagger
stoic imp
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yeah is using the standard dot product for a vector v = (x1,x2,x3,x4)

plush dagger
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Should I do it again or do you understood it ?

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Did

stoic imp
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I mean we need to compute the orthogonal complements correctly

stoic imp
# plush dagger

also is impossible W is dim 1 because it has nontrivial intersection with the orthogonal complement of S and the orthogonal complement of T

plush dagger
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How is that?

stoic imp
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yeah now I need to find basis of S

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when we have basis of S we can compute the orthogonal complement of S

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i) 4x1 + x2 - x4 = 0
ii) x1 + x3 = 0

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ii) x1 + x3 = 0 <==> x1 = -x3

plush dagger
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Yes

stoic imp
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i) 4x1 + x2 - x4 = 0 <==> x4 = 4x1+x2

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x4 = 4x1 + x2 <==> x4 = -4x3 + x2

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(x1,x2,x3,x4)=(-x3,x2,x3,-4x3 + x2)

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S = <(-1,0,1,-4),(0,1,0,1)>

plush dagger
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Perfect

stoic imp
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let v = (x1,x2,x3,x4)

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i) v . (-1,0,1,-4)=0

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i) v . (-1,0,1,-4)=0 <==> -x1+x3-4x4=0

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ii) v .(0,1,0,1)=0 <==> x2 + x4 = 0

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I am trying to find orthogonal complement of S

plush dagger
plush dagger
stoic imp
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-x1 + x3 -4x4 = 0 <==> x1 = x3 - 4x4

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i) x1 = x3 - 4x4
ii) x4 = -x2

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plugging ii) in i)

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x1 = x3 + 4x2

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(x1,x2,x3,x4)=(x3+4x2,x2,x3,-x2)

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orthogonal complement of S is = <(1,0,1,0),(4,1,0,-1)>

plush dagger
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Not -4?

stoic imp
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I plugged ii) in i)

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at first it was x1 = x3 -4x4

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but then it became

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x1 = x3 + 4x2

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because ii) say that x4 = -x2

plush dagger
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True

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My bad

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Nice you're pretty good

stoic imp
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yeah

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orthogonal complement of S is = <(1,0,1,0),(4,1,0,-1)>

plush dagger
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Yep

stoic imp
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,, W \subset S + T \ W \ne S + T \ W \cap S^{\perp} \ne {0} \ W \cap T^{\perp} \ne {0}

jolly parrotBOT
stoic imp
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this are the conditions subspace of R4, named W has to comply

plush dagger
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So you're done?

stoic imp
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well

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We know W has at least one vector from the orthogonal complement of T and one vector at least from the orthogonal complement of S

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and we know W is not a basis for S + T

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but W is entirely contained in S + T

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first let's find a basis of S + T

plush dagger
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Okay

stoic imp
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sorry I was in the toilet

plush dagger
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But I'll find food first

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Np

stoic imp
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ok good

plush dagger
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And you don't need me anyway you're good

pearl pondBOT
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@stoic imp Has your question been resolved?

pearl pondBOT
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@stoic imp Has your question been resolved?

midnight haven
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can anyone help me with calc 1

pure rapids
pearl pondBOT
pearl pondBOT
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@stoic imp Has your question been resolved?

pearl pondBOT
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@stoic imp Has your question been resolved?

summer sundial
stoic imp
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Its intersection of vector subspaces

stoic imp
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S = <(-1,0,1,-4),(0,1,0,1)>

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T = <(-1,1,0,0),(4,0,1,1)>

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,w rref {{-1,1,0,0},{4,0,1,1},{-1,0,1,-4},{0,1,0,1}}

jolly parrotBOT
stoic imp
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S+T=<(-1,1,0,0),(4,0,1,1),(-1,0,1,-4)>

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T orthogonal = <(1,1,-4,0),(0,0,-1,1)>

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orthogonal complement of S = <(1,0,1,0),(4,1,0,-1)>

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,w rref {{1,1,-4,0},{0,0,-1,1},{1,0,1,0},{4,1,0,-1}}

jolly parrotBOT
stoic imp
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S perp ∩ T perp = <(4,1,0,-1)>

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,w rref{{-1,1,0,0},{4,0,1,1},{-1,0,1,-4},{4,1,0,-1}}

jolly parrotBOT
stoic imp
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,w rref {{-1,1,0,0},{4,0,1,1},{-1,0,1,-4},{0,1,0,1}}^T

jolly parrotBOT
stoic imp
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,w rref {{1,1,-4,0},{0,0,-1,1},{1,0,1,0},{4,1,0,-1}}^T

jolly parrotBOT
stoic imp
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,w rref {{4,1,0,-1,0},{1,0,1,0,0}}

jolly parrotBOT
stoic imp
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i) x1 + x3 = 0

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ii) x2 -4x3 -x4 = 0

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x1 = -x3

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x2 = 4x3+x4

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(-x3,4x3+x4,x3,x4)

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(-x3,4x3+x4,x3,x4)=x3(-1,4,1,0)+x4(0,1,0,1)

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S = <(-1,4,1,0),(0,1,0,1)>

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T = <(-1,1,0,0),(4,0,1,1)>

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S + T = <(-1,4,1,0),(0,1,0,1),(-1,1,0,0)>

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,w NullSpace[{{-1, 4, 1, 0}, {0, 1, 0, 1}}]

jolly parrotBOT
stoic imp
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(x-4y, -y, x, y) = x(1,0,1,0) + y(-4,-1,0,1)

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S n T = <(4,0,1,1)>

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S perp = <(1,0,1,0),(-4,-1,0,1)>

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S = <(-1,4,1,0),(0,1,0,1)>

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T = <(-1,1,0,0),(4,0,1,1)>

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,w Nullspace [{-1,1,0,0},{4,0,1,1}}]

jolly parrotBOT
stoic imp
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(-x-y,-x-y,4x,4y) = x(-1,-1,4,0) + y (-1,-1,0,4)

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T perp = <(-1,-1,4,0),(-1,-1,0,4)>

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S n T = <(4,0,1,1)>

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S perp = <(1,0,1,0),(-4,-1,0,1)>

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S = <(-1,4,1,0),(0,1,0,1)>

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T = <(-1,1,0,0),(4,0,1,1)>

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S + T = <(-1,4,1,0),(0,1,0,1),(-1,1,0,0)>

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,w rref {{-1,-1,4,0},{-1,-1,0,4},{1,0,1,0},{-4,-1,0,1}}

jolly parrotBOT
stoic imp
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Sperp n Tperp = <(-4,-1,0,1)>

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,w rref {{-4,-1,0,1},{-1,4,1,0},{0,1,0,1},{-1,1,0,0}}

jolly parrotBOT
stoic imp
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there is something off

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Sperp n T perp I found it correctly

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but when I try to look up the intersection between Sperp n Tperp with S+T the vectors are linearly independent

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wtf man

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there is something that I am missing

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T perp = <(-1,-1,4,0),(-1,-1,0,4)>
S n T = <(4,0,1,1)>
S perp = <(1,0,1,0),(-4,-1,0,1)>
S = <(-1,4,1,0),(0,1,0,1)>
T = <(-1,1,0,0),(4,0,1,1)>
S + T = <(-1,4,1,0),(0,1,0,1),(-1,1,0,0)>

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dim(S+T) = dim(S) + dim(T) - dim(SnT)

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dim(S+T) = 2 + 2 - 1 = 3

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,w rref {{-1,4,1,0},{0,1,0,1},{-1,1,0,0},{1,0,1,0},{-4,-1,0,1}}

jolly parrotBOT
stoic imp
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(S + T) n S perp = <(-4,-1,0,1)>

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,w rref {{-1,4,1,0},{0,1,0,1},{-1,1,0,0},{-1,-1,4,0},{-1,-1,0,4}}

jolly parrotBOT
stoic imp
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T perp = <(-1,-1,4,0),(-1,-1,0,4)>
S n T = <(4,0,1,1)>
S perp = <(1,0,1,0),(-4,-1,0,1)>
S = <(-1,4,1,0),(0,1,0,1)>
T = <(-1,1,0,0),(4,0,1,1)>
S + T = <(-1,4,1,0),(0,1,0,1),(-1,1,0,0)>

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a(-1,-1,4,0)+b(-1,-1,0,4) = c(-1,4,1,0)+d(0,1,0,1)+e(-1,1,0,0)

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(-a-b,-a-b,4a,4b)=(-c-e,4c+d+e,c,d)

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,, \begin{cases} -a-b=-c-e \ -a-b = 4c + d \ 4a = c \ 4b = d \end{cases} \ \begin{cases} -a-b + c + e=0 \ -a-b -4c - d = 0 \ 4a -c = 0 \ 4b -d = 0 \end{cases}

jolly parrotBOT
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why is math so hard anyways?

stoic imp
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,w rref {{-1,-1,1,0,1,0},{-1,-1,-4,-1,0,0},{4,0,-1,0,0,0},{0,4,0,-1,0,0}}

jolly parrotBOT
stoic imp
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,, \begin{cases} a + \frac{5e}{32} = 0 \\ b - \frac{17e}{32} = 0 \\ c + \frac{5e}{8} = 0 \\ d - \frac{17e}{8} = 0 \end{cases}

jolly parrotBOT
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why is math so hard anyways?

stoic imp
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(a,b,c,d,e) = (-5e/32, 17e/32, -5e/8, 17e/8, e)

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a(-1,-1,4,0)+b(-1,-1,0,4) = c(-1,4,1,0)+d(0,1,0,1)+e(-1,1,0,0)

stoic imp
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we can choose e = 32

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and then (a,b,c,d,e) = (-5, 17, -20, 68, 32)

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-5(-1,-1,4,0) + 17(-1,-1,0,4)

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(5,5,20,0)+(-17,-17,0,68)

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(-12,-12,-20,68)

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(-6,-6,-10,34)

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(-3,-3,-5,17)

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T perp = <(-1,-1,4,0),(-1,-1,0,4)>
S n T = <(4,0,1,1)>
S perp = <(1,0,1,0),(-4,-1,0,1)>
S = <(-1,4,1,0),(0,1,0,1)>
T = <(-1,1,0,0),(4,0,1,1)>
S + T = <(-1,4,1,0),(0,1,0,1),(-1,1,0,0)>

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T perp = <(-1,-1,4,0),(-1,-1,0,4)>
S n T = <(4,0,1,1)>
S perp = <(1,0,1,0),(-4,-1,0,1)>
S = <(-1,4,1,0),(0,1,0,1)>
T = <(-1,1,0,0),(4,0,1,1)>
S + T = <(-1,4,1,0),(0,1,0,1),(-1,1,0,0)>

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v = a(1,0,1,0) + b(-4,-1,0,1) , a generic vector of Sperp

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v = (a-4b,-b,a,b)

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a generic vector of S + T

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(a-4b,-b,a,b) = c(-1,4,1,0)+d(0,1,0,1)+e(-1,1,0,0)

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(a-4b,-b,a,b) = (-c-e,4c+d+e,c,d)

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,, \begin{cases} a - 4b + c + e = 0 \ -b - 4c-d-e = 0 \ a -c = 0 \ b - d = 0 \end{cases}

jolly parrotBOT
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why is math so hard anyways?

stoic imp
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,w rref {{1,-4,1,0,1,0},{0,-1,-4,-1,-1,0},{1,0,-1,0,0,0},{0,1,0,-1,0,0}}

jolly parrotBOT
stoic imp
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(a,b,c,d,e) = (-3/10 e, 1/10 e, -3/10 e, 1/10 e, e)

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(a-4b,-b,a,b) = c(-1,4,1,0)+d(0,1,0,1)+e(-1,1,0,0)

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a(1,0,1,0) + b(-4,-1,0,1) = c(-1,4,1,0) + d(0,1,0,1) + e(-1,1,0,0)

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(-3/10).(e,0,e,0) + (1/10).(-4e,-e,0,e) = (-3/10).(-e,4e,e,0) + (1/10).(0,e,0,e) + e(-1,1,0,0)

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(-3).(10e,0,10e,0) + (-40e,-10e,0,10e) = (-3).(-10e,40e,10e,0) + (0,10e,0,10e) + e(-1,1,0,0)

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(-30e,0,-30e,0) + (-40e,-10e,0,10e) = (30e,-120e,-30e,0) + (0,10e,0,10e) + (-e,e,0,0)

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e(-30,0,-30,0) + e(-40,-10,0,10) = e(30,-120,-30,0) + e(0,10,0,10) + e(-1,1,0,0)

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e(-30-40,-10,-30,10) = e(30-1, -120 +10 + 1, -30, 10)

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e(-70,-10,-30,10) = e(29, -109, -30, 10)

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v = (-7, -1, -3, 1)

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T perp = <(-1,-1,4,0),(-1,-1,0,4)>
S n T = <(4,0,1,1)>
S perp = <(1,0,1,0),(-4,-1,0,1)>
S = <(-1,4,1,0),(0,1,0,1)>
T = <(-1,1,0,0),(4,0,1,1)>
S + T = <(-1,4,1,0),(0,1,0,1),(-1,1,0,0)>

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,w rref {{-7,-1,-3,1},{-1,4,1,0},{0,1,0,1},{-1,1,0,0}}

jolly parrotBOT
stoic imp
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a(-1,-1,4,0) + b(-1,-1,0,4) = c(-1,4,1,0) + d(0,1,0,1) + e(-1,1,0,0)

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,, \begin{cases} -a-b+c+e = 0 \ -a-b-4c-d-e = 0 \ 4a-c = 0 \ 4b -d = 0 \end{cases}

jolly parrotBOT
#

why is math so hard anyways?

stoic imp
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,w rref {{-1,-1,1,0,1,0},{-1,-1,-4,-1,-1,0},{4,0,-1,0,0,0},{0,4,0,-1,0,0}}

jolly parrotBOT
stoic imp
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i) a = -3/16 e

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ii) b = 7/16 e

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a(-1,-1,4,0) + b(-1,-1,0,4) = c(-1,4,1,0) + d(0,1,0,1) + e(-1,1,0,0)

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a = -3

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b = 7

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-3(-1,-1,4,0) + 7(-1,-1,0,4)

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(3,3,-12,0) + (-7,-7,0,28)

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(-4,-4,-12,28)

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(-2,-2,-6,14)

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(1,1,3,-7)

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T perp = <(-1,-1,4,0),(-1,-1,0,4)>
S n T = <(4,0,1,1)>
S perp = <(1,0,1,0),(-4,-1,0,1)>
S = <(-1,4,1,0),(0,1,0,1)>
T = <(-1,1,0,0),(4,0,1,1)>
S + T = <(-1,4,1,0),(0,1,0,1),(-1,1,0,0)>

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,w rref {{-1,4,1,0},{0,1,0,1},{-1,1,0,0},{1,1,3,-7}}

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W = <(1,1,3,-7),(-7,-1,-3,1)>

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,, \textbf{Guys I have this subspaces: } \ \mathbb{T}^{\perp} = \langle (-1,-1,4,0), (-1,-1,0,4) \rangle \ \mathbb{S} \cap \mathbb{T} = \langle (4,0,1,1) \rangle \ \mathbb{S}^{\perp} = \langle (1,0,1,0), (-4,-1,0,1) \rangle \ \mathbb{S} = \langle (-1,4,1,0), (0,1,0,1) \rangle \ \mathbb{T} = \langle (-1,1,0,0), (4,0,1,1) \rangle \ \mathbb{S} + \mathbb{T} = \langle (-1,4,1,0), (0,1,0,1), (-1,1,0,0) \rangle \W \cap T^{\perp} \ne {0} \ W \cap S^{\perp} \ne {0} \ W \ne S + T \ W \subset S + T

jolly parrotBOT
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why is math so hard anyways?

stoic imp
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,, \textbf{Guys I have this subspaces: } \ \begin{align} \mathbb{T}^{\perp} &= \langle (-1,-1,4,0), (-1,-1,0,4) \rangle \ \mathbb{S} \cap \mathbb{T} &= \langle (4,0,1,1) \rangle \ \mathbb{S}^{\perp} &= \langle (1,0,1,0), (-4,-1,0,1) \rangle \ \mathbb{S} &= \langle (-1,4,1,0), (0,1,0,1) \rangle \ \mathbb{T} &= \langle (-1,1,0,0), (4,0,1,1) \rangle \ \mathbb{S} + \mathbb{T} &= \langle (-1,4,1,0), (0,1,0,1), (-1,1,0,0) \rangle \ \mathbb{W} &= \langle (1,1,3,-7), (-7,-1,-3,1) \rangle \end{align} \ \textbf{How do I prove the following conditions hold? } \ \begin{align} \mathbb{W} \cap \mathbb{T}^{\perp} &\ne {0} \ \mathbb{W} \cap \mathbb{S}^{\perp} &\ne {0} \ \mathbb{W} &\ne \mathbb{S} + \mathbb{T} \ \mathbb{W} &\subset \mathbb{S} + \mathbb{T} \end{align}

jolly parrotBOT
#

why is math so hard anyways?

stoic imp
#

.close

pearl pondBOT
#
Channel closed

Closed by @stoic imp

Use .reopen if this was a mistake.

stoic imp
#

.reopen

pearl pondBOT
#

stoic imp
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,, \textbf{Guys I have this subspaces: } \ \begin{align} \mathbb{T}^{\perp} &= \langle (-1,-1,4,0), (-1,-1,0,4) \rangle \ \mathbb{S} \cap \mathbb{T} &= \langle (4,0,1,1) \rangle \ \mathbb{S}^{\perp} &= \langle (1,0,1,0), (-4,-1,0,1) \rangle \ \mathbb{S} &= \langle (-1,4,1,0), (0,1,0,1) \rangle \ \mathbb{T} &= \langle (-1,1,0,0), (4,0,1,1) \rangle \ \mathbb{S} + \mathbb{T} &= \langle (-1,4,1,0), (0,1,0,1), (-1,1,0,0) \rangle \ \mathbb{W} &= \langle (1,1,3,-7), (-7,-1,-3,1) \rangle \end{align} \ \textbf{How do I prove the following conditions hold? } \ \begin{align} \mathbb{W} \cap \mathbb{T}^{\perp} &\ne {0} \ \mathbb{W} \cap \mathbb{S}^{\perp} &\ne {0} \ \mathbb{W} &\ne \mathbb{S} + \mathbb{T} \ \mathbb{W} &\subset \mathbb{S} + \mathbb{T} \end{align}

jolly parrotBOT
#

why is math so hard anyways?

autumn trellis
cursive flare
#

I feel like I've seen this question being asked a month ago

cursive flare
#

ask in #latex-help next time
but you can look it up in detexify

swift nymph
#

Oops

stoic imp
# autumn trellis

I was thinking of multiplying the vectors from S = <(-1,4,1,0),(0,1,0,1)> with

let v = (x1,x2,x3,x4)

for example like this:

i) v . (-1,4,1,0) = 0 ==> -x1 + 4x2 + x3 = 0
ii) v . (0,1,0,1) = 0 ==> x2 + x4 = 0

and then, seeing if the vectors from W = <(1,1,3,-7), (-7,-1,-3,1)> satisfy the equations i) and ii) , if one of the vectors satisfy the equations i) or ii) that would mean W = <w1,w2> either w1 or w2 is contained in S perp

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for example if you evaluate w2 = (-7,-1,-3,1) in equation i) and ii) you get

i) 7 -4 -3 = 0 ==> 0 = 0
ii) -1 + 1 = 0 ==> 0 = 0

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so w2 intersects with the orthogonal compĺement of S

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we can do the same for the vectors from T,

iii) v . (-1,1,0,0) =0 ==> -x1+x2 = 0
iv) v . (4,0,1,1) = 0 ==> 4x1 + x3 + x4 = 0

stoic imp
#

,, \textbf{Guys I have this subspaces: } \ \begin{align} \mathbb{T}^{\perp} &= \langle (-1,-1,4,0), (-1,-1,0,4) \rangle \ \mathbb{S} \cap \mathbb{T} &= \langle (4,0,1,1) \rangle \ \mathbb{S}^{\perp} &= \langle (1,0,1,0), (-4,-1,0,1) \rangle \ \mathbb{S} &= \langle (-1,4,1,0), (0,1,0,1) \rangle \ \mathbb{T} &= \langle (-1,1,0,0), (4,0,1,1) \rangle \ \mathbb{S} + \mathbb{T} &= \langle (-1,4,1,0), (0,1,0,1), (-1,1,0,0) \rangle \ \mathbb{S}^{\perp} \cap \mathbb{T}^{\perp} &= \langle (4,1,0,-1) \rangle \ \mathbb{W} &= \langle (1,1,3,-7), (-7,-1,-3,1) \rangle \end{align} \ \textbf{How do I prove the following conditions hold? } \ \begin{align} \mathbb{W} \cap \mathbb{T}^{\perp} &\ne {0} \ \mathbb{W} \cap \mathbb{S}^{\perp} &\ne {0} \ \mathbb{W} &\ne \mathbb{S} + \mathbb{T} \ \mathbb{W} &\subset \mathbb{S} + \mathbb{T} \end{align}

jolly parrotBOT
#

why is math so hard anyways?

stoic imp
#

,w det {{1,1,3,-7},{-7,-1,-3,1},{-1,-1,4,0},{-1,-1,0,4}}

jolly parrotBOT
stoic imp
#

,w det {{1,1,3,-7},{-7,-1,-3,1},{1,0,1,0},{-4,-1,0,1}}

jolly parrotBOT
stoic imp
#

,w det {{1,1,3,-7},{-1,4,1,0},{0,1,0,1},{-1,1,0,0}}

jolly parrotBOT
stoic imp
#

,w det {{-7,-1,-3,1},{-1,4,1,0},{0,1,0,1},{-1,1,0,0}}

jolly parrotBOT
stoic imp
#

dim(W)=2

#

dim(S+T)=dim(S)+dim(T)-dim(SnT)

#

dim(S+T)=2+2-1=3

#

dim(W) < dim(S+T)

#

2 < 3

#

,, 2 \ne 3

jolly parrotBOT
#

why is math so hard anyways?

stoic imp
#

.solved

pearl pondBOT
#
Channel closed

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leaden topaz
#

If I multiply x to the power of 2 what do I get

#

.solved

#

help

warm current
pearl pondBOT
#
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forest gull
#

x | 5 | 8 | 10 | 20
y | 6.4 | 4 | 3.2 | 1.6

inverse direct or neither

forest gull
#

inverse right?

pearl pondBOT
#

@forest gull Has your question been resolved?

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torn sky
#

I just would like to know if my approach here is valid

torn sky
#

Tried my best to recreate it as good as possible in paint lol

pearl pondBOT
#

@torn sky Has your question been resolved?

pearl pondBOT
#

@torn sky Has your question been resolved?

torn sky
#

Should I rephrase?

shadow stag
#

you have to plug it back in and verify that it works though

torn sky
shadow stag
#

because in general, you may get extraneous solutions

#

like technically you would also get x=-10 but plugging it in doesnt give a valid equation

torn sky
#

I've noticed with some of the other tasks indeed, where I got that x = -1, but that would work of course if log10(-1)

#

Yeah exactly, alright

#

On another note maybe

#

If we have 2lg(x)-5lg(x)+6 = 0

Generally with equations, if we substract or add we add to the whole number so we could substract 6 from each side to get 2lg(x)-5lg(x) = -6, but with multiply/divide/root/powers, we have to do that to each term, correct?

#

I'm not sure why I suddenly got that error in my brain, but it suddenly didn't make sense that I substracted only 6 from 1 term

shadow stag
#

you are always doing your operation to do the whole expression on each side

#

and with addition and subtracting, that is equivalent to just doing it to a single thing from each side

torn sky
#

Whereas those other operations do something with 1 value, thus we have to do with with each term

shadow stag
#

whenever you have an equation of the form [expression1] = [expression2], always imagine performing an operation on the whole expressions

#

and then from there you decide whether you use associativity or distributivity

shadow stag
torn sky
# shadow stag what do you mean subtract rom the final number?

So lets say we have what I said earlier, 2lg(x)-5lg(x)+6 = 0, we could in theory subtract or add 6 on both sides, which would just add or remove a 6 from the end product, in this case it makes sense to subtract 6, but if we were to multiply both sides with 2 we would do that with each term, like 2(2lg(x)-5lg(x)+6) = 2*0, where as add or subtract basically adds a new term

#

I hope that explains a bit what I got confused with?

shadow stag
#

yeah you can think of it that way

torn sky
#

Yeah alright, I don't know why I suddenly got that brainfart, but thanks heh

#

.close

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#
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pearl pondBOT
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graceful spruce
#

What did I do wrong ? Find area And perimeter

rose robin
#

you also didn't add it right for the perimeter

#

the individual parts seems right though

graceful spruce
#

How?

#

Area of circle is

#

Pi*r^2:2

rose robin
#

you didn't divide by 2 there

graceful spruce
#

It’s 17,13

#

M

#

Ok got it right

rose robin
graceful spruce
#

Ok thanks

#

.close

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graceful spruce
#

Can anyone tell me all measurements?

Meter
Hekto
Centi

etc.?

urban sun
#

just google

graceful spruce
#

@urban sun what’s corner line?

brisk steeple
#

?

#

What what corner line?

graceful spruce
verbal whale
verbal whale
graceful spruce
graceful spruce
verbal whale
brisk steeple
#

It's not magic

urban sun
#

do you know what ^2 means

brisk steeple
#

It's just directly said

urban sun
#

cm x cm

graceful spruce
#

I think corner line is the yellow line

brisk steeple
#

1m^2 = 1m * 1m = 100cm * 100cm = 10^4 cm^2
1cm^2 = (1/10^4)m^2

graceful spruce
urban sun
graceful spruce
#

Shut up.

#

It’s not elementary if it’s in high school.

urban sun
#

im convinced you are a troll

graceful spruce
#

Then don’t talk to me.

urban sun
#

ye

brisk steeple
#

Ok

graceful spruce
#

Go back to your channel. #help-34

#

.close

pearl pondBOT
#
Channel closed

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graceful spruce
#

You failed all subjects.

#

Quiet it down, Timmy.

#

Yeah right your grade is 1.

#

Lol

#

You’re so funny

#

You can’t even calculate it

pearl pondBOT
#
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#

Please don't occupy multiple help channels.

graceful spruce
#

.close

pearl pondBOT
#
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graceful spruce
#

You’re gonna fail at your life.

verbal whale
#

<@&268886789983436800>

graceful spruce
#

This dude is real enemy of everyone’s enemy.

modest tartan
#

Bro wha going on?

graceful spruce
#

Your whole personality is the definition of rude.

unborn abyss
#

both of you shut up

#

perhaps you'll take a class at uni that teaches you how to be nice

#

when you do, you can come back here

mild berry
#

<@&268886789983436800> i saw what happened why has andrzej not been banned too

graceful spruce
#

Stop going on alt.

mild berry
graceful spruce
#

Because I was attacked first.

unborn abyss
graceful spruce
#

Im allowed to defend myself.

unborn abyss
#

having said that you should just call mods

graceful spruce
mild berry
#

For helping him

#

How does that make sense

#

W moderation

unborn abyss
mild berry
#

Ur just gonna allow this guy to have a false sense of authority over people helping him

#

He told some fella to chop chop

#

And to shut the fuck up and calling ppl worm

#

And thats allowed

#

Nice

brittle pebble
#

ngl, andrzej pasts msg is a bit rude lmao

mild berry
#

Very rude

#

Ngl i understand since he is so poo at maths

verbal whale
mild berry
graceful spruce
#

They had attitude.

#

Over something I didn’t know.

unborn abyss
#

yes, i was looking into those and was going to talk to him in private about that but yall have forced my hand

pearl pondBOT
#
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mild berry
#

Then i get banned for backing my fellow mathematicians against an absolute master of evil

brittle pebble
graceful spruce
#

@mild berry Also stop being invested in this, it’s not concerning you.

verbal whale
graceful spruce
#

Stay on topic.

#

Follow the rules.

mild berry
#

It concerns me i see serious failure of moderation and egregious behaviour

unborn abyss
#

ugh. @graceful spruce yes your behaviour today has been very rude. please remember that helpers are volunteers. the main reason i'm not currently banning you is because this seems to be your first day here and you can learn

#

i see you editing posts btw

brittle pebble
#

the fact that he is new implies that he is most likely a troll

mild berry
#

He joined months ago

graceful spruce
mild berry
#

Is blud tripping

mild berry
#

Nice edit bro

graceful spruce
mild berry
#

Even he agrees he should be banned

graceful spruce
unborn abyss
#

however, i think you can take a break from here for a bit. stay on topic in help channels. i'm closing this. don't talk about this anymore. if you encounter rudeness don't fight back just call mods. is2g

graceful spruce
#

Or sending a meme video in a help channel.

brittle pebble
#

i jsut saw this channel and just went to ur pasts msg and just think its a bit dumb that 2 ppl got banned and not him

unborn abyss
#

.close

pearl pondBOT
#
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graceful spruce
unborn abyss
pearl pondBOT
#
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sharp smelt
#

prove If $\sup(A) < \sup(B)$, show their exists an element $b \in B$, that is an upper bound for $A$

jolly parrotBOT
#

ƒ(Why am. I here)=I don't Know

sharp smelt
#

By definition $sup(A)$ satisfies the two following conditions: It' s an upper bound of $A$, and if any other upper bound exists , it's greater than $\sup(A)$.$\sup(B)$, too, must be an upper bound of $B$, and if any other upper bound exists , it must be greater than $\sup(B)$.
\
Let such an upper bound in $B$ not exist. Thus if there's no element in $B$ satisfying $\sup(A) \leq b$, it must be that $sup(A) > b ; \forall b \in B$. Thus $sup(A) \geq sup(B)$, which contradicts the given condition. Thus our assumption must be wrong, and such an upper bound in $B$ exists

jolly parrotBOT
#

ƒ(Why am. I here)=I don't Know

pearl pondBOT
#

@sharp smelt Has your question been resolved?

sharp smelt
#

<@&286206848099549185>

autumn trellis
sharp smelt
#

Hmm, and that would be the direct proof ?

#

Thanks!

south inlet
sharp smelt
#

Hi eugene, haven't seen you around in a while

#

thanks

#

.close

pearl pondBOT
#
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sharp smelt
#

.reopen

pearl pondBOT
#

sharp smelt
#

I have to show this isn'ttrue if $sup(A) \leq sup(B)$

jolly parrotBOT
#

ƒ(Why am. I here)=I don't Know

sharp smelt
#

I was thinking $A=[0,1]; B=(0,1)$

jolly parrotBOT
#

ƒ(Why am. I here)=I don't Know

spare lark
sharp smelt
spare lark
#

Ah

#

Indeed cuz max(A) > x with x in B

sharp smelt
#

Cool

#

Thanks!

spare lark
#

Ah you was checking what happen when <= ?

sharp smelt
#

yes

spare lark
#

Interesting

sharp smelt
#

That was the next subquestion

spare lark
#

Ok ok then great counterexample

#

Which

#

Works with any x,y since you set A = [x,y] and B = (x,y)

#

y > x

#

And non empty

#

I believe

rare scaffold
#

A=B=(0,1) also works

spare lark
#

Aah

#

Well see

sharp smelt
#

Can I close this channel now

lapis stone
#

Hi

sharp smelt
#

Hi!

#

.close

pearl pondBOT
#
Channel closed

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pearl pondBOT
#
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old oriole
#

Im so confused.. i know it seems easy but im struggling 😭

random ermine
old oriole
#

Ive tried stuff 😭

nimble osprey
random ermine
#

what's the slope of 3x+y=-7

old oriole
#

I have absolutely no idea

random ermine
#

also what r the options on the right

old oriole
#

Its just for a math lib

random ermine
#

what's the slope of y = 2x

old oriole
#

Uhhh

#

Idk 😭

random ermine
#

slope = rise/run

#

change in y / change in x

random ermine
old oriole
random ermine
#

yes

old oriole
#

Or 1

random ermine
#

y = 3x?

old oriole
#

3?

random ermine
old oriole
#

Ohh

random ermine
#

y = 3x + 2

#

?

old oriole
#

Uhhh

#

Would y be 5

random ermine
#

i'm asking for slope

old oriole
#

Oh

#

Uhhh

#

I really dont know 😭

random ermine
#

it's still 3 the +2 doesn't matter

old oriole
#

Oh

random ermine
#

cuz if u shift it up and down it's the same slope

#

+2 is just shifting up by 2 units

old oriole
#

Ohh

random ermine
#

what's the slope of y = mx

#

m is constant

old oriole
#

Hmm

#

Uhhhh

#

-7? 😭

random ermine
#

m

old oriole
#

Im so bad at this im sorry

random ermine
#

we did m=2 and m=3 before

random ermine
#

the slope of y=mx + b is m

random ermine
pearl pondBOT
#

@old oriole Has your question been resolved?

pearl pondBOT
#
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#
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calm wing
#

what?

#

picture on the way?

#

let x be the original price

#

17% were discounted and now it's 340

#

so $x-0.17x = 340$

jolly parrotBOT
#

artemetra

calm wing
#

can you solve for x?

#

precisely

jolly parrotBOT
#

Result:

28220
calm wing
#

yeah you are multiplying by 83 but you should be dividing by 0.83

#

,calc 340/0.83

jolly parrotBOT
#

Result:

409.63855421687
calm wing
#

yes

#

no

#

where did 100 go?

#

$\frac{340}{\frac{83}{100}} = \frac{380\cdot 100}{83}$

jolly parrotBOT
#

artemetra

calm wing
#

you are still supposed to divide by 83

#

not multiply

#

what?

#

how many percent what

#

210% of 3000?

#

ah

#

yes

#

yes

#

divide 52425 by 0.85

#

,calc 52425/0.85

jolly parrotBOT
#

Result:

61676.470588235
calm wing
#

,calc 52425*1.25

jolly parrotBOT
#

Result:

65531.25
calm wing
#

yeah no

calm wing
#

yes, except it's 0.75 in the end

#

so here we have x-0.25x = 52425

#

we get 0.75x = 52425

#

oh cool icelandic

#

indeed

#

yep

#

well 52.425 isn't 25% of the original price, it's 100%-25% = 75% of the original price

#

this is why you use 75

jolly parrotBOT
#

Result:

6.9230769230769e+5
calm wing
#

,w 225000/0.325

calm wing
#

yep

pearl pondBOT
#
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pearl pondBOT
#
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stone imp
pearl pondBOT
stone imp
#

I’m so lost

plush bramble
#

do you know the length of the right side in this picture

sharp condor
#

It's 2x

stone imp
#

Huh

sharp condor
#

4x - 2x

stone imp
#

Oh I shoudve mentioned I already did A

#

It’s B that’s confusing me

sharp condor
#

Cuz u got the 2x on the right and 4x on the left

sharp condor
#

Like a square and a rectangle

stone imp
#

Wdym

lusty merlin
stone imp
#

Yes

lusty merlin
stone imp
#

The bottom part times like going up

#

Idk the words in englihs

lusty merlin
stone imp
#

I do

#

Sorry for late responds my phone died

#

.close

pearl pondBOT
#
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pearl pondBOT
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pearl pondBOT
pine jay
#

What do you think?

#

What do you know about the hypotenuse of a right angle triangle compared to its other sides?

#

?

#

Answer my question

pearl pondBOT
#
Channel closed

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pine jay
#

Bruh

valid peak
#

don't be rude to helpers. either way I'm assuming this is a mute evasion #help-20 message

#

same picture

pearl pondBOT
#
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desert solar
#

$(z-1)(z-3)(z+5)(z+7)=297$ determine the sum of the roots of the equation

jolly parrotBOT
#

Bob Pancakebutter

pearl pondBOT
#

@desert solar Has your question been resolved?

pearl pondBOT
desert solar
#

2

warm current
desert solar
#

with calculations

#

as if x were z

toxic fractal
#

show said calculations?

desert solar
#

$(z-1)(z-3)=z^2-3z-z+3=z^2-4z+3$

jolly parrotBOT
#

Bob Pancakebutter

pearl pondBOT
#
Channel closed

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desert solar
#

.reopen

pearl pondBOT
#

desert solar
#

$(z+5)(z+7)=z^2+7z+5z+35=z^2+12z+35$

jolly parrotBOT
#

Bob Pancakebutter

toxic fractal
#

okay. And why did you split those?

desert solar
#

$(z^2-4z+3)(z^2+12z+35)=297$

storm hatch
#

It may be a good idea to start factorising $297$

jolly parrotBOT
#

如月あやみ Kisaragi Ayami

#

Bob Pancakebutter

desert solar
toxic fractal
brave sluice
#

it might be a good idea

#

maybe the LHS will be 4 integers

pale frost
#

Thats Easy

#

$z^4 + 8z^3 - 10z^2 - 104z - 192 = 0$

jolly parrotBOT
#

BananabrainJoe

pale frost
#

After some calculations you get here

brave sluice
pale frost
#

Then apply Vieta's formulas and you are done !

toxic fractal
storm hatch
#

$$297=11\times3^{3}=(-9)(-3)(3)(1)=(1)(3)(9)(11)$$ then immediately $4$ and $-8$ are solutions

brave sluice
#

when i factored it, i saw that it was not

jolly parrotBOT
#

如月あやみ Kisaragi Ayami

brave sluice
#

oh

#

lol

jolly parrotBOT
#

BananabrainJoe

light helm
#

there's no real need to expand anything

jolly parrotBOT
#

BananabrainJoe

pale frost
brave sluice
#

i gave up too quickly

desert solar
light helm
#

as you aren't required to find the individual roots, just the sum

pale frost
#

Did I do well? @light helm

storm hatch
#

noting that z-1, z+7 and z-3,z+5 form pairs that are centered at $z+2$, just let $y=z+2$ and let the formula for difference of two squares take it from there

#

it's this simple

brave sluice
#

ayami do you claim there are only 2 zeros?

storm hatch
#

no

#

there are 4

light helm
#

note that in vietas formula, sum of roots (for degree 2+) isn't dependent on the constant term

toxic fractal
#

it does require you to expand to get the first and second terms tho

jolly parrotBOT
#

如月あやみ Kisaragi Ayami

light helm
#

e.g consider the sum of roots for
x^2 + 2x + 7 = 0
x^2 + 2x + 13 = 0
x^2 + 2x - 3 = 0
x^2 + 2x + 5 = 0
x^2 + 2x = 0

jolly parrotBOT
#

BananabrainJoe

light helm
#

yes

jolly parrotBOT
#

BananabrainJoe

pale frost
#

Isn't it correct to do the exercise like this?

light helm
#

you could, but I'm hinting at a trick that can do it much faster

pale frost
#

I also think I've found another way

storm hatch
#

Noting that $z-1, z+7$ and $z-3,z+5$ form pairs that are centered at $z+2$ we let $t=z+2$ and thus $$(z-1)(z-3)(z+5)(z+7)=(t-3)(t-5)(t+3)(t+5)=(t^{2}-9)(t^{2}-25)$$\$$=t^{4}-34t^{2}-72=297$$\If you now move everything to the left hand side and factor like a piece-of-cake quadratic you get $$\Rightarrow(t^{2}-36)(t^{2}+2)=0\Rightarrow t={\pm 6,\pm\sqrt{2}i}$$. Plug this back into $t=z+2$ and all four zeroes appear right in front of your eyes like magic.

light helm
#

that the sum of roots of
(z-1)(z-3)(z+5)(z+7)=297
will be the same as
||(z-1)(z-3)(z+5)(z+7)=c||
||(z-1)(z-3)(z+5)(z+7)=0||
and the roots of that and subsequently their sum can be determined quite easily

jolly parrotBOT
#

如月あやみ Kisaragi Ayami

#

BananabrainJoe

desert solar
#

z=-8,4,-2+i√2,-2+i√2?

pale frost
#

You can do it like this too

storm hatch
pale frost
#

@light helm right?

storm hatch
#

-8 is the correct answer

#

you dont have to seek validation from a moderator every step of the process

desert solar
#

The sol Is -8!!!!

pale frost
#

Sorry

light helm
#

I'm not acting as a mod here but as a helper

#

atm

storm hatch
#

icic im just wondering why youre being pinged so much here lol

light helm
#

yes, the sum is -8,
but my point is that this exercise doesn't actually require you to expand everything and/or solve the original equation

pale frost
#

And how is it done?

light helm
#

i've already mentioned above

light helm
#

yes

pale frost
#

z = 1, z = 3, z = -5, z = -7

#

Their sum is -8

light helm
#

yes

pale frost
#

Wait what

desert solar
#

What

#

it was done so quickly

#

But does it do nothing that come out different Z?

light helm
#

sum of roots in
P(z) = 0
is -b/a
constant term doesn't affect that

storm hatch
#

oh yeah, since the zeroes are symmetrical about some C shifting the graph up and down doesn't affect their total sum

#

makes sense

desert solar
#

Thank you all

#

.close

pearl pondBOT
#
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pale frost
#

@light helm One last question, but how did you know if you could use viete if you didn't expand first?

light helm
#

you have a polynomial

pearl pondBOT
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timber parrot
#

How would I solve e!

#

?*

#

help

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crimson bloom
#

The drawing shows a rectangle 𝐴𝐵𝐶𝐷, in which side 𝐵𝐶 is 4 cm long.

On the sides of the rectangle, points 𝐸 and 𝐹 are marked, and segments 𝐸𝐹 and 𝐹𝐶 are drawn so that two identical triangles 𝐸𝐴𝐹 and 𝐹𝐵𝐶 are created. In both triangles, angles of the same measure 𝛼 are marked. Segment 𝐴𝐸 is 3 cm long.

Calculate the area of ​​rectangle 𝑨𝑩𝑪𝑫. Write down the calculation.

crimson bloom
#

I only know one side of triangle...

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<@&286206848099549185>

plush bramble
#

did you try using similar triangles to get an equation for the length of AF or FB

crimson bloom
#

its impossible to do that if i dont have another side...

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@plush bramble

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<@&286206848099549185>

plush bramble
crimson bloom
#

okay then

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AE / CB = AF / FB

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@plush bramble

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<@&286206848099549185>

tall mural
crimson bloom
#

i know..

tall mural
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that's all the information you need

crimson bloom
#

but like i need other sides?

tall mural
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what does EAF being congruent to FBC imply?

crimson bloom
#

i know what it is

tall mural
crimson bloom
#

but i need to know what x will be

#

WHAT am i finding?

#

i only have 2 sides that are the same

tall mural
crimson bloom
#

hold on

#

thse are congruent?

tall mural
#

since EAF and FBC are congruent to each other, then EA = FB = 3 cm and AF and BC = 4 cm.

tall mural
crimson bloom
#

okay

#

bi

tall mural
#

so yes EA = FB

crimson bloom
#

i forgot that i can rotate the triangle

tall mural
#

so you know BC, you can find AF and BF and AB = AF + BF, then you'll have all the information you need to find the area of ABCD

crimson bloom
#

EA / CB = EA / FB

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@tall mural

tall mural
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we are dealing with congruent ones

crimson bloom
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then what now?

tall mural
crimson bloom
#

3 cm / FB = AF / 4 cm

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12 cm = FB*AF

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WOOOHOOO

#

,w 12*4

crimson bloom
#

48 cm^2

tall mural
#

nope

#

you want FB + AF

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not FB*AF

tall mural
crimson bloom
#

so its EAF and FBC

tall mural
#

since EAF and FBC are congruent to each other, you can find FB = EA = 3 cm and AF = BC = 4 cm.

#

so AF + FB = 7 cm = AB

#

since you have AB and BC now, you can find the area of ABCD = 28 cm²

tall mural
crimson bloom
#

i need to find the ratio

#

,calc 4/3

jolly parrotBOT
#

Result:

1.3333333333333
crimson bloom
#

CB is 1.3 times longer than EA

#

.close

pearl pondBOT
#
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pearl pondBOT
#
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river lodge
#

What is the expected value for the number of siblings just by looking at this graph?

terse patrol
#

"The expected value is the mean of the possible values a random variable can take, weighted by the probability of those outcomes."

#

so sum up $\sum_s P_s * s$

jolly parrotBOT
river lodge
#

just by looking at the graph

#

would it be the average of 0 and 2 since they are the same

#

so approx 1

terse patrol
#

wherever the mean of the distribution falls basically, so yeah 1, but slightly to the right because of the extra 0.03

river lodge
#

i see, ok

#

but also, if we were to use calculations, how would it work?

like how exactly do u do "greater than 3"

0(0.36) + 1(0.25) + 2(0.36) + 3(0.03) ... and then?

terse patrol
#

I would just estimate with 3*0.03 for the tail, but you cant get an exact answer without knowing the full distribution

river lodge
#

thanks for ur help

#

.close

pearl pondBOT
#
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pearl pondBOT
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buoyant garnet
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jolly parrotBOT
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plush bramble
#

Missing dr or Delta r

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jolly parrotBOT
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pearl pondBOT
#

@buoyant garnet Has your question been resolved?

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plush bramble
#

You just need to calculate the two volumes and subtract them

#

Volume of sphere of radius a = (4π/3) * a^3

versed mica
#

what riemann said

buoyant garnet
versed mica
#

🤔

jolly parrotBOT
versed mica
#

what

plush bramble
#

I don't know what "did" means

buoyant garnet
#

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plush bramble
#

You have to explain your work

versed mica
#

huh

buoyant garnet
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versed mica
#

lol

buoyant garnet
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versed mica
#

🤔

plush bramble
versed mica
#

brother are you even reading the same question

buoyant garnet
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buoyant garnet
versed mica
#

and a delta r

buoyant garnet
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plush bramble
versed mica
jolly parrotBOT
plush bramble
versed mica
#

$r = a \to r = a +\Delta r$

buoyant garnet
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jolly parrotBOT
buoyant garnet
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versed mica
#

not the same question at all

buoyant garnet
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versed mica
#

just delta r = 1, since 13-12 =1

buoyant garnet
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versed mica
#

as riemann said

#

$V = \frac{4}{3} \pi r^3$

jolly parrotBOT
versed mica
#

and subtract

buoyant garnet
#

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versed mica
#

🤔

versed mica
#

why is there 4pir^2

#

and delta r^2

buoyant garnet
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versed mica
#

and a sitting out there

buoyant garnet
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versed mica
#

you differentiated V for some reason

buoyant garnet
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versed mica
#

not yet

buoyant garnet
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versed mica
#

you don’t?

buoyant garnet
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buoyant garnet
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jolly parrotBOT
buoyant garnet
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plush bramble
#

Then expand and simplify

buoyant garnet
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plush bramble
#

Wut

buoyant garnet
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plush bramble
#

(a+b)^3 = (a^2 + 2ab+b^2) * (a+b)

jolly parrotBOT
plush bramble
buoyant garnet
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jolly parrotBOT
buoyant garnet
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jolly parrotBOT
buoyant garnet
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plush bramble
buoyant garnet
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jolly parrotBOT
buoyant garnet
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plush bramble
#

Yea just cancel and you're done

buoyant garnet
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buoyant garnet
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jolly parrotBOT
plush bramble
#

Left out the factor out front

buoyant garnet
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brave sluice
#

(4/3)pi

buoyant garnet
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brave sluice
#

wait

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back up

brave sluice
buoyant garnet
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brave sluice
#

i don't know i haven't read the question in detail

buoyant garnet
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brave sluice
buoyant garnet
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brave sluice
#

"estimates"?

#

we found an exact formula

buoyant garnet
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brave sluice
#

how does your book describe "linearization"?

buoyant garnet
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brave sluice
buoyant garnet
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brave sluice
#

ah

buoyant garnet
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brave sluice
#

but the derivative where? at a=10?

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brave sluice
#

ah

#

i think i understand

#

you had taken the derivative of the volume earlier, right?

#

what did you get

buoyant garnet
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plush bramble
buoyant garnet
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brave sluice
#

yes

plush bramble
brave sluice
#

and you plug in a for r and multiply by delta r

#

does that sound right?

buoyant garnet
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brave sluice
#

and did it lead you to the answer?

#

where did you get stuck?

buoyant garnet
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brave sluice
#

the process seems correct to me

buoyant garnet
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brave sluice
#

in order to find the value of the derivative at a

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wait

#

that's the answer to the first question

buoyant garnet
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brave sluice
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delta r is meant to be small, so whether you plug in a or a+delta r, it should yield approximately the same value for the derivative

buoyant garnet
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brave sluice
#

in order to find the rise
the derivative is rise / run

#

so you multiply by the run, which is delta r

buoyant garnet
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brave sluice
#

you're welcome

buoyant garnet
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pearl pondBOT
#
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pearl pondBOT
#
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knotty prism
#

I'm taking AP Calc and we were learning about related rates. I wanted to know if I'm on the right track? I have no clue what I'm doing lol

pearl pondBOT
#

@knotty prism Has your question been resolved?

knotty prism
#

No it has not yet

warm current
pearl pondBOT
#
Channel closed

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knotty prism
#

.reopen

pearl pondBOT
#

knotty prism
#

Could u explain what steps I did wrong?

warm current
knotty prism
#

It would be 4

#

So it would be r=h/4?

warm current
#

With that minor correction, you can now express V as a function of h. Then, to relate their rates, you differentiate both sides of your equation with respect to t

knotty prism
#

So for volume I got V=1/48(3.14)(h^3)
3.14 would be pi ofc

#

But im not sure what the nexts steps are, that's where I'm confused

mystic bison
#

if it makes you feel any better related rates is by far the hardest topic in that class

knotty prism
#

It sure is lol

#

Would the next step be like dv/dt = 3/48(3.14)(h^2)?

warm current
#

(Until you get to integral calculus then have fun)

warm current
knotty prism
warm current
#

h is a being considered a differentiatiable function of t. You can call it h(t). So for RHS, you need chain rule

knotty prism
#

Would it look like this?

warm current
knotty prism
#

Nice

#

For the next step would I move to the other side to set the equation to zero?

warm current
knotty prism
warm current