Where Can I Find Helpful Texts on Calculus of Variations?

[Son Goku]

Could anybody recommend any texts on Calculus of Variations?

Unlike most areas of mathematics I'm finding it difficult to obtain standard texts.

 

[dextercioby]

An easy book on the subject is Weinstock's "Calculus of Variations with Applications to Physics and Engineering".

Daniel.

 

[Son Goku]

An easy book on the subject is Weinstock's "Calculus of Variations with Applications to Physics and Engineering".

Daniel.

Thanks. I hit a wall when reading Nakahara's Geometry, Topology and Physics. In chapter 10 he takes the variation of the action of a scalar field and the Einstein-Hilbert action, equates them both to zero and ends up with the Field Equations.

My basic problem is I don't know how to take a variation with respect to a tensor, such as the metric.