1. The problem statement, all variables and given/known data Given a N-dimensional manifold, let gab, be a metric tensor. Compute (i) gabgbc (ii)gabgab Also, just need a clarification on something similar. gcdTcd=gcdTdc=tr T? I'm pretty sure its yes. Probably even a stupid question but a clarification would be useful. 2. Relevant equations 3. The attempt at a solution (i)tr g ? (ii)Here I'm caught between tr g, since I'm thinking its still the tensor and its inverse, and the indices don't matter. The other option is gac. Which is correct?