Question

precalc help please, giving medals and becoming fan!!!
1.) Find the first six terms of the sequence.
a1 = -8, an = 5 • an-1
-8, -40, -200, -1000, -5000, -25,000
-8, -40, -35, -30, -25, -20
0, 5, -40, -35, -30, -25
-40, -200, -1000, -5000, -25,000, -125,000

2.)Find an equation for the nth term of the arithmetic sequence.
-3, -5, -7, -9, ...
an = -3 - 2
an = -3 + -2(n)
an = -3 + -2(n + 1)
an = -3 + -2(n - 1)

Answer 1

For the first one let's get you started.
$$ \Large {a_1=-8
\\ a_2 = 5\cdot a_1= 5 \cdot (\text{-}8) }$$

Answer 2

similarly, to get a3,
plug in n=3 in
\(\Large a_n = 5 a_{n-1} \\ \Large a_3 = 5a_2 = ... ?\)

and so on..

Answer 3

yu are still stuck?

Answer 4

for the second one
-3, -5, -7,- 9....
do you see that we are adding 2 each step

Answer 5

-2 i meant*

Answer 6

so
a1=-3
a2=-3-2=-5
a3=-3-2-2=-7
a4=-3-2-2-2=-9
.
.
.
.
an=-3-2-2-2-2-2-2............-2 (-2 (n-1) times)=3-2(n-1)

Answer 7

correction
an=-3-2(n-1)