What does $p^2_F$ mean in the context of inner product space?

39 Views Asked by At

I'm doing Problem II.3.12 in textbook Analysis I by Amann/Escher.

enter image description here

I can not figure out what $p^2_F$ in (d) actually means. I'm not sure if $p^2_F$ means $p^2_F := p^F \circ p^F$.

My question: What is $p^2_F$?

Thank you for your help!

1

There are 1 best solutions below

0
On BEST ANSWER

Your guess is correct; in this case, $p^2_F$ refers to the composition of $p_F$ with itself (which makes sense only because $F \subset E$).