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linuxux
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I'm presented with this,
[tex](1)\ (\bigcup^{\infty}_{\n=1}A_{n})^{c}\ =\ \bigcap^{\infty}_{\n=1}A_{n}^{c} [/tex]
and asked why induction cannot be used to conclude this.
Now, i know the principle behind induction is to show that P(S)=N by showing that when
(i) S contains 1 and
(ii) whenever S contains a natural number n, it also contains n+1.
So I assume somewhere along the line (1) can't fit into either (i) or (ii), but I'm just not getting it. Help please, thanks.
I also have some trouble understanding infinity in general. My text says that, notationally,
[tex](2)\ \bigcup^{\infty}_{\n=1}A_{n}[/tex]
is just another way of saying the set whose elements consist of any element that appears in at least one particular (An), but, in a previous question, we already proved with induction that
[tex](3)\ (A_1\ \cup\ A_2\ \cup\ A_3\ \cup\ ...\ \cup\ A_n)^c\ =\ A^{c}_{1}\ \cup\ A^{c}_{2}\ \cup\ A^{c}_{3}\ \cup\ ...\ \cup\ A^{c}_{n}[/tex]
In my mind, (3) should lead to (1), and since we used induction on (3) to extrapolate to (1), then we did use induction to prove (1), but obviously, this is incorrect and I am not sure why?
[tex](1)\ (\bigcup^{\infty}_{\n=1}A_{n})^{c}\ =\ \bigcap^{\infty}_{\n=1}A_{n}^{c} [/tex]
and asked why induction cannot be used to conclude this.
Now, i know the principle behind induction is to show that P(S)=N by showing that when
(i) S contains 1 and
(ii) whenever S contains a natural number n, it also contains n+1.
So I assume somewhere along the line (1) can't fit into either (i) or (ii), but I'm just not getting it. Help please, thanks.
I also have some trouble understanding infinity in general. My text says that, notationally,
[tex](2)\ \bigcup^{\infty}_{\n=1}A_{n}[/tex]
is just another way of saying the set whose elements consist of any element that appears in at least one particular (An), but, in a previous question, we already proved with induction that
[tex](3)\ (A_1\ \cup\ A_2\ \cup\ A_3\ \cup\ ...\ \cup\ A_n)^c\ =\ A^{c}_{1}\ \cup\ A^{c}_{2}\ \cup\ A^{c}_{3}\ \cup\ ...\ \cup\ A^{c}_{n}[/tex]
In my mind, (3) should lead to (1), and since we used induction on (3) to extrapolate to (1), then we did use induction to prove (1), but obviously, this is incorrect and I am not sure why?
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