Question

find the sum of first n terms of the g.p 256,64,16....
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Answer 1

Answer:

Wait ........................

Answer 2

Answer:

$s = \frac{1024}{3} (1 - {( \frac{1}{4} )}^{n} )$

Step-by-step explanation:

$s = 256 + 64 + 16 + ....n \: terms$

Here a = 256

r = 64/256 = 1/4

$so \: s = \frac{a(1 - {r}^{n}) }{1 - r}$

$or \: s = \frac{256(1 - ( { \frac{1}{4} })^{n} )}{1 - \frac{1}{4} }$

$or \: s = 256 \times \frac{4}{3} (1 - ( { \frac{1}{4} )}^{n} )$

$or \: s = \frac{1024}{3} (1 - {( \frac{1}{4} )}^{n} )$