Question

Find the sum of first n terms of the G.P. 256,64,16

Answer 1

HELLO DEAR,

GIVEN:-

a = 256,

r = t2/t1 = 64/256 = 1/4 ≠ 1

now,

Sn = a(rⁿ - 1)/(r - 1)

= 256{(1/4) - 1}/{(1/4) - 1}

= 256{(1/4)n - 1}/(-3/4)

= 256(-4/3){(1/4)ⁿ - 1}

Sn = (-1024/3){(1/4)n - 1}

Sn = (1024/3){1 - (1/4)ⁿ}

I HOPE IT'S HELP YOU DEAR,

THANKS