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Assertion: Let veca and vecb be any two ...

Assertion: Let `veca and vecb` be any two vectors `(vecaxxhati).(vecbxxhati)+(vecaxxhatj).(vecxxhatj)+(vecaxxhatk).(vecbxxhatk)=2veca.vecb., Reason: (veca.hati)(vecb.hati)+(veca.hatj)(vecb.hatj)+(veca.hatk)(vecb.hatk)=veca.vecb.` (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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Assertion: |veca+vecb|lt|vec-vecb| , Reason: |veca+vecb|^2=a^2+b^2+2veca.vecb. (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.

Assertion: |veca|=|vecb| does not imply that veca=vecb , Reason: If veca=vecb,then |veca|=|vecb| (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.

Assetion: (vecaxxvecb)xx(veccxxvecd)=[veca vecc vecd]vecb-[vecb vecc vecd]veca Reason: (vecaxxvecb)xxvecc=(veca.vecc)vecb-(vecb.vecc)veca (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.

Assertion : If |veca|=2,|vecb|=3|2veca-vecb|=5, then |2veca+vec|=5, Reason: |vecp-vecq|=|vecp+vecq| (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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Assertion: If vecx xx vecb=veccxxvecb and vecxd_|_veca then vecx=((vecbxxvecc)xxveca)/(veca.vecb) , Reason: vecaxx(vecbxxvecc)=(veca.vecc)vecb-(veca.vecb)vecc (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.

Assertion: vecc4veca-vecb and veca,veb,vecc are coplanar. Reason Vector veca,vecb,vecc are linearly dependent. (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.

Assertion: Let veca=hati+hatj and vecb=hatj-hatk be two vectors. Angle between veca+vecb and veca-vecb=90^0 Reason: Projection of veca+vecb on veca-vecb is zero (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.

Assertion: In a /_\ABC, vec(AB)+vec(BC)+vec(CA)=0 , Reason: If vec(AB)=veca,vec)BC)=vecb then vec(C)=veca+vecb (triangle law of addition) (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.

Assertion: vecr.veca and vecb are thre vectors such that vecr is perpendicular to veca vecrxxveca=vecbrarrvecr=(vecaxxvecb)/(veca.veca) , Reason: vecr.veca=0 (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.