What is the angle between 2a and 4a?

What is the angle between 3a and -5a? What is the ratio of magnitude of two vectors?

What is the angle between a and -(3)/(2) a .

What is the angle between hour hand and minute hand at 2:25 pm?

.If the angle between the vectors a and "b" is (pi)/(3) , then what is the angle between -5a and 6b ? "

What is the angle between hour-hand and minute-hand as 2 : 25 pm?

What is the angle between the plane 2x-y-2z+1=0 and 3x-4y+5z-3=0 ?

What is the angle between two planes 2x-y+z=4 and x+y+2z=6 ?

What is the angle between the lines whose direction cosines are proportional to (2,3,4) and (1,-2,1) respectively?

What is the angle between the lines whose direction cosines are proportional to (2,3,4) and (1,-2,1) respectively