Write the first five terms of the sequence defined recursively.

Question

a₁ = 19 ,  a_{k + 1} = (−3)a_k

_{find terms a1, a2, a3, a4, a5}

Answer 1

The easiest way to do these problems is to think of a_k+1 as the next term and a_k as the term before it. So to find a₂ you multiply the term before it by -3 to get (19) (-3) = -57.

Then to find a₃ multiply this number by -3 to get (-57) (-3) = 171

Then to find a₄ multiply this number by -3 to get (171) (-3) = -513

Then to get a₅ multiply this number by -3 to get (-513) (-3) = 1539