kill(all);

     A Wonderful Closure on D_Alembert

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infix("-->");

D_Alemberts_Paradox --> zero_airfoil_drag$

airfoil --> Joukowski$

(Joukoski) --> (phi + 1/phi);

phi --> (a+b*%i);

(e^z) --> sum(z^n/n!,n,1,n);

sum(z^n/n!,n,1,n) --> Ratio_Test;

Ratio_Test --> D_Alemberts_Ratio_Test;

van=facebook.com/LearningCalculus$

Prove cosh(ix) = cos(x);

cosh(%i*x);

Prove -i*sinh(ix) = sin(x);

-%i*sinh(%i*x);