| (a) | (i) Give an example of an element of Z+. (ii) Give an example of an element of Q. (iii) Give an example of an element of Q Ç Z-. (iv) Is the following relationship true or false?
You must justify your answer.
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[1] [1] [1] [1] |
| (i) Any correct answer eg. 5 |
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| (ii) Any correct answer eg. 1/2 |
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| (iii) Any correct answer e.g -3 |
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| (iv) False. e.g. -p
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| (b) | Given matrics A =  and B =  ,Calculate (i) AB (ii) ABT
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[3] [2] |
| (i) AB = 
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| (ii) ABT = 
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| (c) | Write negations for each of the following
statements: (i) Lee is six feet tall and he weighs at least 90kg. (ii) The bus was late or Edwin's watch was slow. |
[2] [2] |
(i)
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| (ii) The bus was not late and Edwin's watch was not slow.
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| (d) | A student council consists of 15 students. In
how many ways can a committee of six be selected from the committee?
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[3] |
| 15C6
or 5005
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| (e) | Let A = {2,3,4} and B= {6,8,10} and define a
binary relation R from A to B as follows:
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| (i) Is 4 R 6? Justify your answer. (ii) Is (2,10)Î R? Justify your answer. |
[2] [2] |
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| (i) 4 R 6 is not true
since 4 does not divide 6.
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| (ii) (2,10) Î R is
true since 2 does divide exactly into 10.
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