Exercise 7.C.13

Answers

Proof. It is false. Let e1,,en be an orthonormal basis of V and define Sej = e1 for j = 1,,n. Then ||Sej|| = 1 for each ej, but obviously S is not invertible, therefore S is not an isometry (7.42 requires isometries to be invertible). □

User profile picture
2017-10-06 00:00
Comments