Suppose $K$ is the closed convex hull generated by the canonical basis $\{e_n\}$ in $\mathcal{l}_2$. How do you find the unique closest to $0$ in $K$?
I don't have the foggiest idea about how to do that? Any references will be appreciated.
Suppose $K$ is the closed convex hull generated by the canonical basis $\{e_n\}$ in $\mathcal{l}_2$. How do you find the unique closest to $0$ in $K$?
I don't have the foggiest idea about how to do that? Any references will be appreciated.
Hint: What is the norm of $\dfrac{e_1+e_2+\cdots+e_n}{n}$?