The only place in Maple where symbolic calculations can be made with vectors is in the Physics:-Vectors package. Unfortunately, linear input for this package works best, although the output reflects notation greatly desired in the realm of physics.
In the following calculations, the basis vectors take the place of the vectors T, N, and B, respectively. Within the package, a left-underscore for the letters i, j, or k indicates a unit basis vector ; a right-underscore, a symbolic vector.
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Use the Setup command to implement the notational benefits of the package.
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Let R2 represent , where the right- underscore indicates that this is a vector in the package.
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Let R3 represent , where the right- underscore indicates that this is a vector in the package.
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R3_ := a[3]*_i+b[3]*_j+c[3]*_k;
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Let R4 represent , where the right- underscore indicates that this is a vector in the package.
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R4_ := a[4]*_i+b[4]*_j+c[4]*_k;
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Use the period for the dot product and &x for the cross product. Apply the expand command. The result is the value of the box product.
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q := expand(R2_ . (R3_ &x R4_));
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Apply the simplify command to the result of the substitutions enacted by the eval command. Both and must be set as Atomic Identifiers to prevent Maple from actually taking a derivative, which by default, is with respect to .
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Write this final result as .
Slightly more insight into the details of these calculations can be obtained if, instead of using the basis vectors , the derivatives of R are written in terms of T, N, and B.
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r2_ := b[2]*N_:
r3_ := a[3]*T_+b[3]*N_+c[3]*B_:
r4_ := a[4]*T_+b[4]*N_+c[4]*B_:
expand(r2_ . (r3_ &x r4_));
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The simplification of the box product to a new product involving just the vectors of the TNB-frame, and not linear combinations of these vectors, is the reward for this extra effort.