Answer:
60°
Step-by-step explanation:
the angle Θ between vectors a and b is
cosΘ = = = = , then
Θ = ( ) = 60°
cos θ= 60°
cos θ= a . b/।a। ।b।
=15/2/3×5
=15/30
=1/2
cos θ=cos60°
θ=60
B) 0:15=0