Recent content by Mamooie312

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    Undergrad Nonexistence of the universal set.

    Yo. Wsup. I watched a video about three years ago where this guy suppossedly provedthe nonexistence of the universal set. I can't find it now but what he said (rather quickly) was that from Cantor, every set is a subset. Therefore, there is no universal set. 1) Is this valid? 2) RW...
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    College Concerns: What Should I Expect?

    Urbana-Champaign does.
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    Finding the Unit Normal Vector at t=0: A Headache-Inducing Problem

    Normal vector (dot) Tangent vector = 0 usually if you don't care about the binormal ones.
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    Compute Integral Using Jacobian Det in Polar Coordinates

    T: (x,y) to (theta, r) x = rcostheta y = rsintheta derivative matrix of T: t11 = -rsintheta t12 = costheta t21 = rcostheta t22 = sintheta detT = -r(sintheta)(squared) - r(costheta)(squared) = -r but the Jacobian should just be r and if you map T: (x,y) to (r, theta) instead of what I did then it...
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    Absolute Max Min Problem on Region Bounded by x = \sqrt{1-y^2}, y=x, and y=0

    Use Lagrange Multipliers on the boundaries.
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    Compute Integral Using Jacobian Det in Polar Coordinates

    Homework Statement Determine the Jacobian determinant for "polar" coordinates and use that to compute the intergral . . . Blah blah blah that's not the point. Homework Equations (x,y) maps by T to (r, theta) or (theta, r) detT = jacobian The Attempt at a Solution Anyways, first I...
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    Finding a Basis for Subspace in R^4: Linear Algebra Tips

    If the determinant of the matrix these vectors make is 0 then some of them are linearly dependent.
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    Finding the intersection of subspaces, and addition of subspaces

    E + F = span{u,2v) + span{w,v} = au + 2bv + cw + dv = span(u,v,w) I think. Not comepletely sure.
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    Calculating the Coefficient of Friction on a 4.8m Slide Inclined at 28 Degrees

    You forgot gravity. F = mgsin(28) - umgcos(28) = ma Solve for acceleration and then use kinematics. Proof: Friction = uN Normal force is gravity going into slide = umgcos(28) All movement is along the slide. The gravity component in this direction is mgsin(28) Try to treat gravity and the...
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    Frictionless ramp question. Find angle.

    Only force on the mass is gravity, which is conservative. so Einitial = Efinal Ui + Ki = Uf + Kf