Norma operatora, iniekcja, suriekcja zad. 2.
: 6 kwie 2015, o 23:59
Wyznaczyć normę operatora \(\displaystyle{ A}\), sprawdzić, czy \(\displaystyle{ A}\) spełnia warunki iniekcji, suriekcji oraz czy jest to operator otwarty:
a) \(\displaystyle{ A:(\mathbb{R}^{2},\parallel \cdot \parallel_{ \infty }) \rightarrow (\mathbb{R}^{3},\parallel \cdot \parallel_{ 2 })}\), \(\displaystyle{ A(x_{1},x_{2})=(x_{1}+2x_{2}, x_{1}-x_{2}, 3x_{1}+x_{2})}\)
b) \(\displaystyle{ A:(\mathbb{R}^{3},\parallel \cdot \parallel_{ 1}) \rightarrow (\mathbb{R}^{2},\parallel \cdot \parallel_{ \infty })}\), \(\displaystyle{ A(x_{1},x_{2},x_{3})=(x_{1}+x_{2}, x_{1}+x_{3})}\)
c) \(\displaystyle{ A:c \rightarrow l^{ \infty }}\), \(\displaystyle{ A(x_{1}, x_{2}, x_{3},...)=(x_{1}, \frac{3}{2}x_{2}, \frac{5}{3}x_{3},..., \frac{2n-1}{n}x_{n},...)}\)
d) \(\displaystyle{ A:l^{ \infty } \rightarrow c_{0}}\), \(\displaystyle{ A(x_{1}, x_{2}, x_{3},...)=(x_{1}, \frac{x_{2}}{2}, \frac{x_{3}}{3},...)}\).
a) \(\displaystyle{ A:(\mathbb{R}^{2},\parallel \cdot \parallel_{ \infty }) \rightarrow (\mathbb{R}^{3},\parallel \cdot \parallel_{ 2 })}\), \(\displaystyle{ A(x_{1},x_{2})=(x_{1}+2x_{2}, x_{1}-x_{2}, 3x_{1}+x_{2})}\)
b) \(\displaystyle{ A:(\mathbb{R}^{3},\parallel \cdot \parallel_{ 1}) \rightarrow (\mathbb{R}^{2},\parallel \cdot \parallel_{ \infty })}\), \(\displaystyle{ A(x_{1},x_{2},x_{3})=(x_{1}+x_{2}, x_{1}+x_{3})}\)
c) \(\displaystyle{ A:c \rightarrow l^{ \infty }}\), \(\displaystyle{ A(x_{1}, x_{2}, x_{3},...)=(x_{1}, \frac{3}{2}x_{2}, \frac{5}{3}x_{3},..., \frac{2n-1}{n}x_{n},...)}\)
d) \(\displaystyle{ A:l^{ \infty } \rightarrow c_{0}}\), \(\displaystyle{ A(x_{1}, x_{2}, x_{3},...)=(x_{1}, \frac{x_{2}}{2}, \frac{x_{3}}{3},...)}\).