Question

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Write an
explicit formula for An, the nth term of the sequence 32, 25, 18, ....

Answer 1

`\bold{a_n=-7n+39}`

Explanation:

25 - 32 = -7 and 18 - 25 = -7

It means an arithmetic sequence with common difference d = -7

`a_n = a_1+d(n-1)\\\\a_1=32\\d=-7\\\\a_n=32+(-7)(n-1)\\\\a_n = 32-7n+7\\\\\underline{a_n=-7n+39}`