Q8 of 50 Page 26

Prove that the arithmetic sequence with first term 1/3 and common difference 2/3 contains all odd numbers, but no even number.

For the sequence,


a =


d =


an = a + (n-1) × d


= + (n-1) ×


=


= k(2n-1) (where k = constant)


As an is a multiple of (2n-1) and not (2n) it contains all odd numbers but no even number..


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The Bird problem in Class 8 (The lesson, Equations) can be slightly changed as follows.

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