Question

if the resultant of two unequal vectors is equal to sum of their magnitudes what is the angle between vectors ?

Answer 1

Let  A and B  be two unequal vectors and θ be the angle between them.Therefore according to given :

A+B=√(A²+B²+2ABcos θ)

Squaring on both sides, we get

(A+B)²=A²+B²+2ABcos θ

A²+B²+2AB=A²+B²+2ABcos θ

2AB=2ABCosθ

Cosθ=1

∴ Cosθ=Cos0°

∴  θ=0°

Answer 2

Answer:

0 degree

Explanation: R=A+B(A is not equal B)

A+B=√(A²+B²+2ABcos θ)

Squaring on both sides, we get

(A+B)²=A²+B²+2ABcos θ

A²+B²+2AB=A²+B²+2ABcos θ

2AB=2ABCosθ

Cosθ=1

∴ Cosθ=Cos0°

∴  θ=0°