Let `vea, vecb and vecc` be unit vectors such that `veca.vecb=0 = veca.vecc`. It the angle between `vecb and vecc is pi/6` then find `veca`.

Explanation

We have `veca.vecb = veca .vecb =0`
This implies that `veca` is perpenedicular to both `vecb and vecc`. Thus, `veca` is a unit vector, perpendicular to both `vecb and vecc`.Hence,
`vecr = +-(vecb xx vecc)/(|vecbxxvecc|) = +-(vecbxxvecc)/(|vecb||vecc|sinpi//3)`
` = +- 2 (vecb xx vecc)`