Question

The tick one questions
viii and the x​

Answer 1

Answer:

see below

Step-by-step explanation:

(viii) since....

-a/1 = a^2/-a = -a

It's a GP with a = 1 and r = -a

now....

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

Sn = 1[1-(-a)^n]/[1-(-a)]

Sn = 1 + a + a^2 + .....a^(n-1) [if n is odd]

(x) since...

-1/7 = 1/7/-1 = -1/7

it's a GP with a = 7 & r = -1/7 ; r<1

now....

S = 1/(1-r)

S = 1/1-(-1/7)

S = 7/8