Question

If angle between two vectors A & overline B is 0 and if| overline A |=| overline B | ( overline A + overline B ) and ( overline A - tilde B ) then angle between Solve problem by
(1) Non Graphical Method
(2) Graphical Method​

Answer 1

Answer:

From the diagram, we have A+B=R

Thus, R2=A2+B2+2ABcosθ

or, B2/2=A2+B2+2ABcosθ   --- (1)

Also, A is perpendicular to R

Thus, A.(A+B)=0 or, A2+ABcosθ=0

which gives, A=−Bcosθ

Put this in (1) to get 

B2cos2θ+B2/2−2B2cos2θ=0

or, cos2θ=1/2 or cosθ=21, giving θ=450

Explanation:

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