If vector |a| = 12 cm, |b| = 13 cm, and the angle between them when placed tail to tail is 35°, find a • b to the nearest centimetre

Question

If vector |a| = 12 cm, |b| = 13 cm, and the angle between them when placed tail to tail is 35°, find a • b to the nearest centimetre
	a)	
a • b = 57
	b)	
a • b = 8
	c)	
a • b = 11
	d)	
a • b = 24

drwls · Answer

Tail to tail, the dot product is 12 * 13 cos 35 = 127.78 cm^2 Round that off as requested. It is an area, not a length.