===== Determinant via multilinear functionals ===== ==== Set ==== | @#55CCEE: context | @#55CCEE: $V$ ... finite dimensional $\mathcal F$-vector space | | @#FFBB00: definiendum | @#FFBB00: $\mathrm{det}:L(V,V)\to \mathcal F$ | | @#DDDDDD: range | @#DDDDDD: $n\equiv \mathrm{dim}(V)$ | | $M\in \mathrm{MultiLin}(V^n)$ | | $ v_1,\dots,v_n\in V $ | | $A\in L(V,V)$ | | @#55EE55: postulate | @#55EE55: $ M(A\ v_1,\dots,A\ v_n) = \mathrm{det}(A)\cdot M(v_1,\dots,v_n) $ | ==== Discussion ==== === Theorems === * The determinant is an invariant of linear operators on finite-dimensional vector spaces. * $\mathrm{det}(AB)=\mathrm{det}(A)\cdot \mathrm{det}(B)$ * $\mathrm{det}(Id)=1$ * $\mathrm{det}(A)\ne 0$ is $A$ is a linear isomorphism * $\mathrm{det}(A)\ne 0\Rightarrow \mathrm{det}(A^{-1})=\mathrm{det}(A)^{-1}$ === Reference === Wikipedia: [[http://en.wikipedia.org/wiki/Determinant|Determinant]] ==== Parents ==== === Context === [[Multilinear functional]], [[Linear operator algebra]], [[Vector space dimension]]