Question

Let b = 4i + 3j and c be two vectors perpendicular to each other in the xy-plane. All vectors in the same plane having projections 1 and 2 along b and c respectively, are given by ...

Answer 1

Let 

4x + 3y = 5 ...(i)

Also, projection of a along c is 2 

3x – 4y = 10 ...(ii)

Solving (i) and (ii), we get,

x = 2, y = – 1

Hence, the required vector is

2i - j