Find curl(a X f ) a=a(sub1) i + a(sub2) j +a(sub3) k f=x i + y j +z k
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If memory serves then $\displaystyle \left| \begin{array}{ccc} i & j & k \\ a_1 & a_2 & a_3 \\ x & y & z \end{array} \right|= i(a_2z-a_3y)-j(a_1z-a_3x)+k(a_1y-a_2x)$
Originally Posted by pickslides If memory serves then $\displaystyle \left| \begin{array}{ccc} i & j & k \\ a_1 & a_2 & a_3 \\ x & y & z \end{array} \right|= i(a_2z-a_3y)-j(a_1z-a_3x)+k(a_1y-a_2x)$ That is $\displaystyle a\times f$. scubasteve123 still needs to take the curl. But it is far simpler to recognise that, because a is a constant vector, $\displaystyle \nabla\times (a\times f)= a\times (\nabla\times f)$.
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