If the momenta of two particles of a system are given by `vecp_(1)=2hati-hatj+3hatk` and `vecp_(2)=-hati+2hatj-2hatk` then calculate the angle made by the direction of motion of the system with positive x-axis.

Explanation

For system `vecp-vecp_(1)+vecp_(2)=(2hati-hatj+3hatk)+(-hati+2hatj-2hatk)=hati+hatj+hatk`
Let angle made by x-axis be `alpha` then `cos alpha=(1)/sqrt(3)rArralpha=cos^(-1)((1)/sqrt(3))`