The value of `[{(81)^(-1/2)}^(-1/4)]^2`

The value of [[(2401)^(-1//2)]^(-1//4)]^(2) is

((81)^(-2))^(1/4)=

(i) 81^(1/2)

The value of root 4((81)^(-2)) is

Find the value of (4cos^(2)9^(@)-1)(4cos^(2)27^(@)-1) (4cos^(2)81^(@)-1)(4cos^(2)243^(@)-1) .

Find the value of (1)/(81^(n))-(10)/(81^(n))^(2n)C_(1)+(10^(2))/(81^(n))^(2n)C_(2)-(10^(3))/(81^(n))^(2n)C_(3)+...+(10^(2n))/(81^(n))

The value of (1)/(81^(n))-(10)/(81^(n)).""^(2n)C_(2)-(10^(3))/(81^(n)).""^(2n)C_(3)+…+((10)^(2n))/(81^(n)) is