The value of `cospi/11+cos(3pi)/11+cos(5pi)/11+cos(7pi)/11+cos(9pi)/11` is

The value of 2(cos pi/11 + cos(3pi)/11 + cos(5pi)/11 + cos(7pi)/11 + cos(9pi)/11) is……….

The value of cos""(pi)/(11)+cos""(3pi)/(11)+cos""(5pi)/(11)+cos""(7pi)/(11)+cos""(9pi)/(11), is

The value of (cos pi)/(11)+(cos(3 pi))/(11)+(cos(5 pi))/(11)+(cos(7 pi))/(11)+(cos(9 pi))/(11)

If the value of "cos"pi/15"cos"(2pi)/15"cos"(3pi)/15"cos"(4pi)/15"cos"(5pi)/15"cos"(6pi)/15"cos"(7pi)/15 is (1)/(2^(k)) , then which of the following is true ?

cos(pi)/(11)+cos(3 pi)/(11)+cos(5 pi)/(11)+cos(7 pi)/(11)+cos(9 pi)/(11)=(1)/(2)

The value of 2"cos"(pi)/(13)"cos"(9pi)/(13)+"cos"(3pi)/(13)+"cos"(5pi)/(13) is

The value of cos""(pi)/(9)cos""(2pi)/(9)cos""(3pi)/(9)cos""(4pi)/(9), is

Find the value of cos^2. pi/16+cos^2. (3pi)/16+cos^2. (7pi)/16 .