Question

Help one question geometric series

Answer 1

@student_basil can you please help me with this last question please

Answer 2

please i relaly need help with this last question anyone that could help it would be great THnak :)

Answer 3

use the formula for sum of n terms o f a GP

Sn = a* ( 1 - r^n)
-------
1 - r

where a = first term and r = common ration

Answer 4

okay let me set it uo sn is what 7 right?

Answer 5

n = 7 and r = -5

Answer 6

a= -11

Answer 7

oh yes sorry a = -11

Answer 8

is it a -143231

Answer 9

right

Answer 10

thanks :)

Answer 11

there was no need to use the last term

Answer 12

yw