The value of `cos(pi/19)+cos((3pi)/19)+cos((5pi)/19)+`......`+cos((17pi)/19)` is (a)`1/2` (b)...
3,150 views · Published 12 October 2018 · 8:34 · Indexed 2 October 2026
Channel: Doubtnut · 2018 · Education
To ask Unlimited Maths doubts download Doubtnut from - https://goo.gl/9WZjCW The value of `cos(pi/19)+cos((3pi)/19)+cos((5pi)/19)+`......`+cos((17pi)/19)` is (a)`1/2` (b)0 (c)1 (d)none
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