Does order of the components in a set matter?

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enter image description here$A=\{ a,b,c \}$ $B= \{a,c,d\}$

$A\times B=\{ (a,a),(a,c),(a,d),(b,a),(b,c),(b,d),(c,a),(c,c),(c,d)\}$ $B\times A= \{ (a,a),(a,b),(a,c),(c,a),(c,b),(c,c),(d,a),(d,b),(d,c)\}$

i want to intersect this two sets.

$(A \times B) \cap (B \times A)=$ ???

my question is, is $(c,b)$ and $(b,c)$ the same thing? because, if they are same I am going to have the different result in comparison to if they are not same.

If not why?

this is the original question. I am solving b.

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No, they are not the same.

By definition, $$(a,b)=(c,d)\iff a=c \wedge b=d$$

and so $(a,b)\not=(b,a)$ for $a\not=b$.

2
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The answer to your title: Do order of $\require{cancel}\bcancel{\text{compenents}}$ elements in a set matter?

No. A set is an unordered collection of elements. $\{fred,wilma,barney,betty\}=\{betty,wilma, fred,barney\}$ because order does not matter.

The answer to your body: is $(c,b)$ and $(b,c)$ the same thing?

No. $A\times B$ is defined to be a set of ordered pairs. $(c,b)$ is not an unordered set but is an ordered pair. $(c,b) \ne (b,c)$.