# If #A= <-3 ,4 ,-1 ># and #B= <8 ,-4 ,2 >#, what is #A*B#?

##### 1 Answer

Mar 1, 2016

#### Explanation:

given 2 vectors

# ula = (x_1,y_1,z_1) " and ulb=(x_2,y_2,z_2)# then

#ula . ulb = (x_1xxx_2)+(y_1xxy_2)+(z_1xxz_2)# here

#A = (x_1,y_1,z_1) = (-3,4,-1)# and

# B =(x_2,y_2,z_2) = (8,-4,2 )#

#rArr A . B = (-3xx8)+(4xx-4)+(-1xx2) # = - 24 - 16 - 2 = - 42