nilai dari sin50+sin40/cos50+cos40

2sin45cos10/2cos45cos10
= 1

(sin 50 + sin 40)/(cos 50 + cos 40)
= (2 sin (50+40)/2 cos (50-40)/2) / (2 cos (50+40)/2 cos (50-40)/2)
= (2 sin 45 cos 5) / (2 cos 45 cos 5)
= (sin 45) / (cos 45)
= (1/2 √2)/(1/2 √2)
= 1