Question

Find the first 5 terms of the sequence: a1 = 2, an = -3an-1

Answer 1

okay this one is a bit trickier, but i think you can still do it!

Answer 2

So, I though a2 would be 3 but, that didn't work. @robz8

Answer 3

a2 = -3(a1)... so what is a1 again?

Answer 4

Is it like this:
\[a _{n} = -3a _{n-1}\]

Answer 5

It says a1 is 2

Answer 6

yes, so if a1 is 2... and a2 = -3 * 2..... what would that make a2?

Answer 7

a2 would be -6? @robz8

Answer 8

correct, so now that a2 = -6, the next part in the function is a3 = -3(a2)

so what would a3 be?

Answer 9

-27? @robz8

Answer 10

nooooooo... not quite, try again.

we know that a2 is -6,

so a3 = -3*(-6)

Answer 11

but is it written like how i wrote it? @Emilyh117 because the notation counts.

Answer 12

Oooooo. It would be 18. @robz8

Answer 13

there we go... now repeat that pattern 2 more times, and you have the first 5 terms of the recursive equation

Answer 14

Okay. I started the next one and got -54. Then I got 162. @robz8

Answer 15

that is correct! now you have the first 5 terms of the recursive equation!

Answer 16

Yay! Thank you! :) @robz8

Answer 17

yw! @Emilyh117