Question

for a G.P S5=1023 ,r=4 find a​

Answer 1

Answer:

a=3

Step-by-step explanation:

Given'

summatin of first 5 G.P series, S5=1023

and common ratio, r=4

• summation of G.P terms having n number of terms =$\frac{a\times(r^n -1)}{r-1}$

hence, summation of first five terms = $\frac{a\times(r^5 -1)}{r-1}$

                                                   1023  = $\frac{a\times(4^5 -1)}{4-1}$

                                                      a=$\frac{1023\times 3}{4^5 -1}$

                                                       a=3  

Answer 2

summatin of first 5 G.P series, S5=1023

and common ratio, r=4

summation of G.P terms having n number of terms =\frac{a\times(r^n -1)}{r-1}

r−1

a×(r

n

−1)

hence, summation of first five terms = \frac{a\times(r^5 -1)}{r-1}

r−1

a×(r

5

−1)