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Thread: Q: Let S = {1,2,5,6 } Define a relation R on S of at least four order pairs, as (a,b

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    Q: Let S = {1,2,5,6 } Define a relation R on S of at least four order pairs, as (a,b

    Q: Let S = {1,2,5,6 }
    Define a relation R on S of at least four order pairs, as (a,b)  R iff a*b is even (i.e. a multiply by b is even)
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    Re: Q: Let S = {1,2,5,6 } Define a relation R on S of at least four order pairs, as

    Since multiplying any integer by an even integer results in an even integer, you just need to make sure that if (x,y) is in R, then at least one of x or y is even. For example, it would be okay to have (2,5) in R, but it wouldn't be okay to have (1,5) in R. There are lots of choices for R here. For example, we could let R={(1,2),(2,1),(2,2),(2,5)}.
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    Re: Q: Let S = {1,2,5,6 } Define a relation R on S of at least four order pairs, as

    Please solve my question in proper method.

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    Re: Q: Let S = {1,2,5,6 } Define a relation R on S of at least four order pairs, as

    Quote Originally Posted by sMilips View Post
    Please solve my question in proper method.
    Surely you are in no position to make a demand? So who is to say what is proper?

    $\mathcal{R}=[\mathit{S}\times\{2,6\}]\cup[\mathit{S}\times\{2,6\}]^{-1}$
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    Re: Q: Let S = {1,2,5,6 } Define a relation R on S of at least four order pairs, as

    Quote Originally Posted by Plato View Post
    Surely you are in no position to make a demand? So who is to say what is proper?

    $\mathcal{R}=[\mathit{S}\times\{2,6\}]\cup[\mathit{S}\times\{2,6\}]^{-1}$
    I mean solve in suitable method.

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    Re: Q: Let S = {1,2,5,6 } Define a relation R on S of at least four order pairs, as

    Quote Originally Posted by sMilips View Post
    I mean solve in suitable method.
    You asked for our help, did you not?
    Then you demand a different more "standard" answer. I asked who you were to do that.
    Then I gave you the complete answer that accounted for the 'iff' part of your question.
    But you seem to not understand even that correct answer.
    Please be more attentive to correct answers in the future.
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    Re: Q: Let S = {1,2,5,6 } Define a relation R on S of at least four order pairs, as

    Quote Originally Posted by DrSteve View Post
    Since multiplying any integer by an even integer results in an even integer, you just need to make sure that if (x,y) is in R, then at least one of x or y is even. For example, it would be okay to have (2,5) in R, but it wouldn't be okay to have (1,5) in R. There are lots of choices for R here. For example, we could let R={(1,2),(2,1),(2,2),(2,5)}.
    But 2x5=10 and 2x2=4.. 5 and 4 are not members of given set.

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    Re: Q: Let S = {1,2,5,6 } Define a relation R on S of at least four order pairs, as

    Quote Originally Posted by sMilips View Post
    But 2x5=10 and 2x2=4.. 5 and 4 are not members of given set.
    That has nothing to do with the posted question.
    Quote Originally Posted by sMilips View Post
    Q: Let S = {1,2,5,6 }
    Define a relation R on S of at least four order pairs, as $(a,b) \in R \iff a\cdot b\text{ is even}$ (i.e. a multiply by b is even)
    .
    BUT the if an only if requires that the entire relation be listed.
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