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Question
Let < an > be a sequence. Write the first five term in the following:
a1 = 1, an = an − 1 + 2, n ≥ 2
Solution
a1 = 1, an = an − 1 + 2, n ≥ 2
\[a_2 = a_1 + 2 = 1 + 2 = 3\]
\[ a_3 = a_2 + 2 = 5\]
\[ a_4 = a_3 + 2 = 7\]
\[ a_5 = a_4 + 2 = 9\]
Hence, the five terms are 1, 3, 5, 7 and 9.
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