Find the number of terms in the progression `4, 2, 1, …,(1)/(128).`

Answer

N/a

Explanation

`"Here "a=4,r=(2)/(4)=(1)/(2)`
`"Let "T_(n)=(1)/(128)`
`rArr" "acdotr^(n-1)=(1)/(128)`
`rArr" "4xx((1)/(2))^(n-1)=(1)/(128)`
`rArr" "((1)/(2))^(n-1)=(1)/(4xx128)=((1)/(2))^(9)`
`rArr" "n-1=9`
`rArr" "n=10.`