( sin 60 + cos 120 ) ( cos 330 -sin 210 )
=(sin 60+ cos(180-60))*(
cos(360-30)-sin(180-30))
= (sin60-cos60)*(cos30+sin30)
=(½√3-½)(½√3+½)
=(½√3)²-½²
=¼*3-¼=½
" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
( sin 60 + cos 120 ) ( cos 330 -sin 210 )
=(sin 60+ cos(180-60))*(
cos(360-30)-sin(180-30))
= (sin60-cos60)*(cos30+sin30)
=(½√3-½)(½√3+½)
=(½√3)²-½²
=¼*3-¼=½