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3, 12, 21, ...
Find the 43rd term.

1 Answer

5 votes

Answer:


\sf \t_(43) = 381381

Explanation:

Arithmetic sequence:

3,12,21 ..........

Find the common difference.

Common difference = second term - first term

d = 12 -3


\sf \boxed{\bf d = 9}


\sf \boxed{\bf t_n = a + (n-1)*d}

n = 43 ; d = 9 ; a = 3


\sf t_(43)=3 + (43-1)*9\\\\

= 3 + 42*9

= 3 + 378

= 381

User Alexandre Hamez
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