Question

Find the first six terms of the sequence. A1 = -6, an = 4 an-1

Answer 1

Given a1 = -6 ---( 1 )

$a_{n} = 4a_{n-1}$

i)if n = 2

$a_{2} = 4a_{2-1}$

=$4a_{1}$

= $4\times(-6)$

= -24

ii)if n=3

$a_{3} = 4a_{3-1}$

=$4a_{2}$

= $4\times(-24)$

= -96

iii)if n=4

$a_{3} = 4a_{4-1}$

=$4a_{3}$

= $4\times(-96)$

= -384

iv)if n=4

$a_{4} = 4a_{4-1}$

=$4a_{3}$

= $4\times(-384)$

= - 1536

v)if n=5

$a_{5} = 4a_{5-1}$

=$4a_{4}$

= $4\times(-1536)$

= - 6144

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