Recent content by mercuryman

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    Undergrad Linear transformation from [-1,1] to [a,b]

    Hey This is from Numerical analysis course (Legendre polynom) - they gave us the polynomial transformation from [-1,1] to [a,b] as: x = 2/(b-a) * z - (b+a)/(b-a) what is the proof of this tranformation? where did it come from? thanks
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    Finding the Inverse of a Rational Function

    Homework Statement Find the inverse function of y= x/2 - 5/2x Homework Equations The Attempt at a Solution I've tried to manipulate the equation to find x(y) without any sucsses.
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    Proving 3/4 is Infimum of A: A = { x^2 +x + 1 }

    Homework Statement Giva a formal proof that 3/4 is the infimum of the set : A = { x^2 +x + 1 } Homework Equations I need a clear way to prove it - to understand the contradiction. The Attempt at a Solution I've assumed there is a M<3/4 that x^2 +x + 1>M. where is the contradiction?
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    Proving |xy-ab| is Less Than Epsilon: Absolute Value Question | Homework Help"

    Homework Statement Given: |x-a|<ε |y-b|<ε. proove: |xy-ab|<ε(|a|+|b|+ε) Homework Equations I need a direction for this proof. The Attempt at a Solution I tried by the info: -ε+a<x<ε+a and -ε+b<y<ε+b to ,multiply these inequalities, but it's not true. and i tried with the...
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    Undergrad 3 Differential Equations problems

    Hey Can I have your help with: 1. (2e^y - X)y'=1 y(0)=0 y(x)=? 2. xyy' + y^2 - x^2 = 0 3. x^2y' - 1 = cos2y lim y(x) = π/2 x->+∞ thanks
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    How to calculate the fourth vertex of a parallelogram

    given 3 vectors : a=(1,3,4) b=(2,5,3) c=(1,0,0)