Question

The angle between (A+B) & (Ax Β)
a) 0
b) π/4
c) π/2
d) π​

Answer 1

I hope it's a question about VECTORS !

Given,

A and B are two vectors. So, their sum A+B lies in the same plane where A and B lie (Since they are non -parallel so they define a plane and the cross product between them is not zero).

A × B=∣A∣ ∣B∣ sinα (n) , where α is the angle between A & B and n is the unit vector perpendicular to the plane containing A & B. So, the angle between (A+B) and (A×B) is 90°

Mathematically,

∣A+B∣ ∣A×B∣ cosα = (A+B).(A×B)

= A.(A×B) + B.(A×B)

= B.(A×A) + A.(B×B)

= 0 + 0 = 0

Hence, angle between (A+B) & (AxB) is π/2 ___________ (Ans.)