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(a) |
(i) Consider the circle relation C
defined for all (x, y) Î Â x Â, such that -1< x, y < 1, |
[3] |
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(x, y) Î C « x2 + y2 = 1 |
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Is C a function? Why? |
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(ii) Consider the relation L
defined for all (x, y) Î Â x Â, |
[3] |
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(x, y) Î L « y = x - 1 |
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Is C a function? Why? |
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(b) Consider the relation |
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B = { (x, y) Î N x N : | x - y | < 2 } |
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Is the relation |
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(i) reflexive? |
[2] |
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(ii) symmetric? |
[2] |
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(iii) transitive? |
[2] |
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(iv) an equivalence? |
[1] |
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Explain your answers. |
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(c) Consider the relation R represented
by the following matrix |
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Is the relation |
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(i) reflexive? |
[2] |
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(ii) symmetric? |
[2] |
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(iii) transitive? |
[2] |
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(iv) an equivalence? |
[1] |
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Explain your answers. |
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