How do you express sin(π12)cos(7π12) without products of trigonometric functions?

2 Answers
Jul 1, 2018

12+34

Explanation:

sin(π12)=3122
cos(7π12)=3122

sin(π12)cos(7π12)=(3122)2

(3122)2=18(31)2=38+3418=12+34

Jul 1, 2018

324

Explanation:

sin(π12)cos(7π12)

https://lo.wikipedia.org/wiki/%E0%BB%84%E0%BA%95%E0%BA%A1%E0%BA%B8%E0%BA%A1

(12)(sin(π12+7π12)+(sin(π12)(7π12))

(12)(sin(2π3)+sin((π2))

(12)(sin(π3)sin(π2))

(12)(321)

324