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guidance, flight mechanics and trajectory optimization

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once again due to Dynamic Programming concepts.) The number of additions<br />

performed in the previous problem were 66 for the second table, <strong>and</strong> 11 for<br />

the third table - for a total of 77 additions, The "brute force" method<br />

would require the calculation of S = Xl2 t 2X22 + X32 for all possible<br />

permutations of xl, x2, <strong>and</strong> x3 where 05 Xi5 10, + x2 t x3 = 10,<br />

<strong>and</strong> Xi is an integer. For this particular problem the "f brute force"<br />

method requires 66 cases or 132 additions. It is seen that even on this<br />

simple problem the savings in additions is quite significant.<br />

In order to compare <strong>and</strong> contrast the Dynamic Programming solution of<br />

this problem with the classical solution, the same problem will not be<br />

solved using classical techniques. First, the constraint equation is joined<br />

to the original problem by a Lagrange Multiplier,<br />

Now the partial derivatives are taken with respect to the independent<br />

variables <strong>and</strong> equated to zero.<br />

This yields<br />

2s<br />

- =2x,--h =o<br />

a x,<br />

h<br />

x, = -<br />

2<br />

2<br />

3 = 7<br />

A<br />

x3 = -<br />

2<br />

39<br />

(2.2.29)<br />

(2.2.30a)<br />

(2.2.30b)<br />

(2.2.30~)<br />

(2.2.31a)<br />

(2.2.3lb)<br />

(2.2.31~)

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