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Known arithmetic sequence 2, 5, 8, 11. Find the number of item 599?
Because 5-2 = 3, 8-5 = 3, so D is the leading formula of 3 arithmetic sequence, an = a1 + (n-1) d, so A599 = 2 + (599-1) 3 = 1796, all mobile phones are "very hard", hope to adopt it!
Known arithmetic sequence 2,5,8,11,14... Q 98 is the number one of them
98 = 2 + 3x = 32 item 32
The arithmetic sequence 5,8,11. And the arithmetic sequence 3,8,13. All have 100 items, so how many items are there in the same two sequences
The sequence 1 is an = 3N + 2, n = 1, 2.100
Sequence 2 is BN = 5m-2, M = 1, 2.100
Let an = BM,
That is 3N + 2 = 5m-2,
5m-4=3n
The mantissa of 5 m must be 0 or 5, and the mantissa of 5 M-4 must be 1 or 6
The 100th term of arithmetic sequence 1 is 302, and the 100th term of arithmetic sequence 2 is 498
So the same term has the second, seventh, twelfth, seventeenth, twenty-two, twenty-seven, thirty-two, thirty-seven of the first sequence,
42,47,52,57,62,67,72,77,82,87,92,97, 20 items in total,
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- 1. If the arithmetic sequence 5,8,11,... And 3,7,11,... Have 100 terms, then the number of terms of their same terms is___ . But I don't understand. Please tell me, ∵3(4n-1)+2≤a100=302 ∴n≤25.
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