Question

Prove that sin⁡〖20°〗 sin⁡〖40°〗 sin⁡〖60°〗 sin⁡〖80°〗=3/16

Answer 1

Step-by-step explanation:

$answer \\ \\ sin20. \: sin \: 40. \: sin60. \: sin80 \\ </p><p>=> \: sin \: 60 \: [sin20. \: sin \: 40.sin \: 80 \: ] \\ </p><p>=> \: √3/2 \: [sin20. \: sin \: (60-20) \: .sin \: (60+20)] \\ </p><p> => \: √3/2 \: [sin \: 3 \: (20)/4] \\ </p><p>=> \: √3/2 \: [sin 60/4] \\ </p><p>=> \: √3/2 \: [√3/2*4] \\ </p><p>=> \: √3/2*√3/8 \\ </p><p>= \: 3/16 \\ </p><p>$