Recent content by andmcg

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    Prove that every number b can be written b = f(a)

    Homework Statement I am trying to learn how to write proofs and this proof seems weird... Suppose f o g = I. Prove that every number b can be written b = f(a) for some number a. Homework Equations f(g(x))=I(x)=x The Attempt at a Solution Here's my stab at it. Let g(x)=a...
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    Proving the Identity Function: Composed Functions

    Suppose that f composed with g equals g composed with f for all functions g. Show that f is the identity function. I really just don't know where to start.
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    Area moment of inertia of a triangle

    Homework Statement What is the moment of inertia WRT to the x-axis (Ix) of a right triangle with base b and height h where the legs of the triangle coincide with the x and y axis? It would be helpful to know both the single integral and double integral method. Homework Equations Ix=int(y^2 dA)...
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    Differential equations problem

    Homework Statement A curve with Cartesian equation y=f(x) passes through the origin. Lines drawn parallel to the coordiante axes through and arbitrary poing of the curve form a rectangle with two sides on the axes. The curve divides every such rectangle into two regions A and B, one of which...
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    Eliminate Parameters to Find Ellipsoid Cartesian Equation

    Homework Statement Eliminate the parameters u and v to obtain a Cartesian equation, thus showing that the given vector equation represents a portion of the surface named. Also, compute the fundamental vector product dr/du x dr/dv in terms of u and v.Homework EquationsEllipsoid r(u,v) =...