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Statement-1: cos10^(@)+cos20^(@)+…..+cos...

Statement-1: `cos10^(@)+cos20^(@)+…..+cos170^(@)=0`
Statement-2: `cos alpha+cos(alpha+beta)+....+cos(alpha+(n-1)beta)=(cos(alpha+((n-1)beta)/(2))sin((nbeta)/(2)))/(sin((beta)/(2))), beta ne 2npi.`

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