SOLUTION: the 3rd term of a linear sequence is twice the 1st term and the 8th term of the sequence is four more than the 6th term. find the first term of the arithmetic progression.
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-> SOLUTION: the 3rd term of a linear sequence is twice the 1st term and the 8th term of the sequence is four more than the 6th term. find the first term of the arithmetic progression.
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Question 1085662: the 3rd term of a linear sequence is twice the 1st term and the 8th term of the sequence is four more than the 6th term. find the first term of the arithmetic progression. Answer by ikleyn(52788) (Show Source):
Since "the 8th term of the sequence is four more than the 6th term", it implies that the common difference is half of 4, i.e. d = 2.
Since "the 3rd term of a linear sequence is twice the 1st term", it means that
= , or
= .
Hence, = 4.
Thus the first term of the AP is 4 and the common difference is 2.
Solved.
Notice that the term "linear sequence" is out of use. The canonical term is Arithmetic progression on Arithmetic sequence.
