19.3.21 Linear Operators

Condition: Determine at which \ (\ LEFT (\ LAMBDA_ {1}, \ LAMBDA_ {2}, \ LDOTS \ RIGHT) \) Operator \ (A: L_ \ RIGHTARROW L_ {2}, \ QuADA (X_ LET x_ {2}, \ ldots \ right) = \ left (\ lambda_ {1} x_ {1}, \ lambda_ {2} x_ {2}, \ ldots \ right) \) is limited and find its norm in this case.