The value of the expresion `E=sum_(r=1)^17 1/((1+cot^4(10theta)^@)` equaals

The value of the expresion E=sum_(r=1)^(17)(1)/((1+cot^(4)(10 theta)^(@))) equaals

The value of the expression sum_(theta =0)^8 1/(1 + tan^3 (10theta)^@) equals

The value of the expression sum_(theta =0)^8 1/(1 + tan^3 (10theta)^@) equals

The value of the expression sum_(theta=0)^(8)(1)/(1+tan^(3)(10 theta)^(@)) equals

then the value of the expression E=(sqrt(1+tan^(2)theta))/(tan theta)-(sqrt(1+cot^(2)theta))/(cot theta) is equal to

The value of sum_(r=1)^(10)r(n C_(r))/(n C_(r-1)) =

The value of sum int_(r=1)^(r=10)rC(10,r) is

The value of sum_(r=1)^(10)rP(r,r) is

The value of cot (sum_(n=1)^(23) cot^(-1) (1 + sum_(k=1)^(n) 2k)) is