If `x=9^(1/3)9^(1/9)9^(1/27)......oo`,`y=4^(1/3)4^(-1/9)4`,`z=sum_(r=1)^(oo)(1+i)^(-r)` ,then arg `(x+yz)` is equal to:

If x=9^(1/3) 9^(1/9) 9^(1/27) ......ad inf y= 4^(1/3) 4^(-1/9) 4^(1/27) ...... ad inf and z= sum_(r=1)^oo (1+i)^-r then , the argument of the complex number w = x+yz is

Prove that 9^(1//3)xx9^(1//9)xx9^(1//27)xx...oo=3 .

If a = sum_(r=1)^(oo) 1/(r^(2)), b = sum_(r=1)^(oo) 1/((2r-1)^(2)), then (3a)/b is equal to _____

sum_(r=1)^(oo)(2r-1)|(9)/(11)|^(r) is equal to

Prove that (9(1)/(3).9^((1)/(9)).9^((1)/(77)).........oo)=3

sum_(r=1)^9 tan^-1(1/(2r^2)) =

P=3^((1)/(3))3^((2)/(9))3^((3)/(27))...oo, then P^((1)/(3)) is

The vlaue of 9^(1//3)xx9^(1//9)xx9^(1//27)xx………oo is :

If S=sum_(n=2)^(oo)(3n^(2)+1)/((n^(2)-1)^(3)) then (9)/(4S) is