Question

1

Answer 1

The common ratio is -16/8 = -2
Check this formula out.

\( \color{Black}{\Rightarrow S = a \times \Large {1 - r^n \over 1 - r} }\)

Answer 2

a is the first term.
r is the common ratio.
n is the number of terms.

Answer 3

Replace a with 8.
Replace r with -2.
Replace n with 15.

Answer 4

\( \color{Black}{\Rightarrow SUM = 8 \times \Large{1 - (-2)^{15} \over 1 - (-2)}}\)

Answer 5

\( \color{Black}{\Rightarrow 8 \times \Large {1 + 2^{15} \over 3}}\)

Answer 6

Can you calculate this by using a calculator?

Answer 7

\[2^{15} = 2^{10} \times 2^5 = 1024*32\]

Answer 8

Yes, thank you both very much!

Answer 9

You're welcome!