Hi, I was about to calculate the limit

limit(sin(x)+sin(y),{x=0,y=0})

and Maple 17 returns the same expression, with no answer.

What I am doing wrong?

I was working with the computation of the eigenvectors of a 3X3 symmetric matrix with algebraic entries and Maple 17 doesn´t give me an answer after a long time, even with CUDA activated. You can see this by the commands below:

Can I create an tensor in the Physics package in Maple 16 with a free index like i=1..N:

A[mu,1]:=A[mu]

A[mu,2]:=B[mu]

.

.

.

and so on? The index is not one of the type gauge, spacetime or spinor.

Can you expalin the difference between the gaugeindices, spinorindices,and spacetimeindices in the Physics package in Maple 16? 

How can I plot on the same graph the Normal,Tangent and Binormal vectors from a Position Vector?

Thanks