The value of 3 cosec20°-sec20°cos20°cos40°cos60°cos80° is equal to: [2026]
(1)
E=3sin20°-1cos20°12·14·cos60°
=3cos20°-sin20°cos20°.sin20°·16
=(32cos20°-12sin20°)32×22cos20°.sin20°
=sin40°sin40°×64=64