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Find the 4th term if the sequend in which a1 = 2 and an+1 = -4an + 2.

User Gregori
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1 Answer

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the notation, more or less indicates that, the first value in the sequence is 2, the next term's value, will be "current value, times -4 and plus 2"

thus
\bf \begin{array}{ccllll} a_n\ term&&value\\ \text{\textemdash\textemdash\textemdash}&&\text{\textemdash\textemdash\textemdash}\\ a_1&&2\\ a_2&-4a_1+2&-4(2)+2\implies -6\\ a_3&-4a_2+2&-4(-6)+2\implies 26\\ a_4&-4a_3+2&-4(26)+2\implies -102 \end{array}
User Bill Doughty
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