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Assertion : If in a /\ABC, vec(BC)=vecp/...

Assertion : `If in a /_\ABC, vec(BC)=vecp/|vecp|-vecq/|vecq|` and vec(AC)=(2vecp)/|vecp|,|vecp|!=|veq|` then the value of `cos2A+cos2B+cos2C ` is -1., Reason: If in `/_\ABC, /_C=90^0 then cos2A+cos2B+cos2C=-1` (A) Both A and R are true and R is the correct explanation of A (B) Both A and R are true R is not te correct explanation of A (C) A is true but R is false. (D) A is false but R is true.

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