Question

Determine o vigèssimo termo da P.A (3,10;17...)

Answer 1

$P.A (3,10;17...)\\\\ a_1=3\\ n=20\\ r=7\\ a_n=a_{20}=?\\\\ a_n=a_1+(n-1)*r\\\\ a_{20}=3+(20-1)*7\to \\ a_{20}=3+19*7\to \\ a_{20}=3+133\to \\ a_{20}=136$

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