Vector Geometry Question help please! I  have the d) part as my doubt the question is on this weblink- http://img834.imageshack.us/img834/6990/30528189.png   Please provide adequate information...

Vector Geometry Question help please!

I  have the d) part as my doubt the question is on this weblink-

http://img834.imageshack.us/img834/6990/30528189.png

 

Please provide adequate information to comprehend(it isn't homework help but my exams are coming so I need it)

 

Thank you very much for your kind support!:)

Asked on by muskan-a

1 Answer | Add Yours

pramodpandey's profile pic

pramodpandey | College Teacher | (Level 3) Valedictorian

Posted on

In fig dirction of AB is not assigned. Also dirction  of OX and CB is missing. We try to answer keeping your answer in view and assign direction acordingly.

Let direction of AB is A to B .

(a).  By triangle law  ,OB is resultant of vectors OA and AB

OA+AB=OB

AB=-OA+OB

   =-a+b

(b).   Ax=(1/4)AB

          = (1/4)(-a+b)

         =-(1/4)a+(1/4)b       (scalar multimultiplication).

(c).  Dircetion of  BC is  B to C

So again by triangle law for resulatant of vectors,

               BA+AC=BC

             -AB+AC=BC           (BA=-AB)

              BC= -(-a+b)+mb

                 = a-b+mb

                 =a+(m-1)b

(d).        OX parallel to BC

           OX=OA+AX

               =a+(-1/4)a+(1/4)b

               =(3/4)a+(1/4)b

         OX= n. OB

       (3/4)a+(1/4)b =n( a+(m-1)b)

                            =na+n(m-1)b

Compare the coefficients  of a and b

              n=3/4

           n(m-1)=1/4

           (3/4)(m-1)=1/4  

                3(m-1)=1

                   m-1=(1/3)   

                   m=1+1/3=4/3     

 

We’ve answered 318,983 questions. We can answer yours, too.

Ask a question