Question 1177010
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Hi
{{{a[n] = a[1]*r^(n-1)}}}
{{{a[2] = a[1]*r^(n-1)}}} = 1  
          {{{a[1] = 1/r }}}   0r r = {{{ 1/a[1]}}}
{{{a[5] = a[1]*r^(n-1)}}} = 1/8
            {{{(a[1])* (1/a[1])^4 = 1/8 }}}   {{{a[1]}}} = 2
  2r = 1 , r = 1/2

 2(1/2)^4 = 1/8  checks
Wish You the Best in your Studies.
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