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It is known that {an} is an arithmetic sequence, A1 = 2, A2 = 3. If three numbers are inserted between every two adjacent terms to form a new arithmetic sequence with the number of the original sequence, we can find: (1) what is the 12th term of the original sequence? (2) What is the 29th item of the new sequence?
(1) {an} is an arithmetic sequence, A1 = 2, A2 = 3. If three numbers are inserted between every two adjacent terms to form a new arithmetic sequence with the number of the original sequence, it can be recorded as {BN}, then {BN} is a sequence with 2 as the first term and 3 as the fifth term. Let {an} tolerance be D, and {BN} tolerance be d ', then 2 + D = 3
It is known that {an} is an arithmetic sequence, A1 = 2, A2 = 3. If three numbers are inserted between every two adjacent terms to form a new arithmetic sequence with the number of the original sequence, we can find: (1) what is the 12th term of the original sequence? (2) What is the 29th item of the new sequence?
(1) {an} is an arithmetic sequence, A1 = 2, A2 = 3. If three numbers are inserted between every two adjacent terms to form a new arithmetic sequence with the number of the original sequence, it can be recorded as {BN}, then {BN} is a sequence with 2 as the first term and 3 as the fifth term. Let {an} tolerance be D, and {BN} tolerance be d ', then 2 + D = 3
In the arithmetic sequence {an}, A1 = - 5, A2 = - 1 / 2, if a number is inserted between every two adjacent terms of the modified sequence to make it still an arithmetic sequence, a general term formula of the new arithmetic sequence is obtained
a1=-5,a2=-1/2
d=a2-a1=4.5
If a number is inserted between two adjacent items to make it still an arithmetic sequence, the tolerance of the new sequence is as follows:
d=4.5/2=2.25
a1=-5
an=a1+(n-1)d=-5+2.25(n-1)=2.25n-7.25
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