Question

sum of two vectors is also a unit vector. their difference is........​

Answer 1

Answer:

∣

a

+

b

∣=1

∣

a

∣

2

+∣

b

∣

2

+2∣

a

∣∣

b

∣cosθ

=1

→2(1+cosθ)=1

→cosθ=

2

−1

θ=120

∘

∣

a

+

b

∣=

∣

a

∣+∣

b

∣

2

−2∣

a

∣∣

b

∣cosθ

=

1+1−2cos120

∘

=

2+2×

2

1

=

3

.