nilai dari sin100+sin20/cos250+cos190 adalah

(sin 100° + sin 20°)/(cos 250° + cos 190°)
= (2 sin (100°+20°)/2 cos (100°-20°)/2) / (2 cos (250+190)/2 cos (250-190)/2)
= (2 sin 60° cos 40°) / (2 cos 220° cos 30°)
= (2 . 1/2 √3 cos 40°) / (2 cos 220° 1/2 √3)
= (cos 40°) / (cos (180° + 40°))
= (cos 40°) / - cos 40°
= -1