#P_1(8,4,1) " "P_2(6,0,2)#
#P_"1x"=8" "P_"2x"=6" "Delta P_x=6-8=-2#
#P_"1y"=4" "P_"2y"=0" "Delta P_y=0-4=-4#
#P_"1z"=1" "P_"2z"=2" "Delta P_ z=2-1=2#
#" distance between the point of " P_1" and " P_2" is:"#
#Delta x=sqrt((Delta P_x)^2+(Delta P_y)^2+(Delta P_z)^2)#
#Delta x=sqrt((-2)^2+(-4)^2+2^2)=sqrt (4+16+4)=sqrt24#
#v=(Delta x)/t#
#v=sqrt 24/2#
#v=sqrt (4*6)/2#
#v=(cancel(2)*sqrt6)/cancel(2)#
#v=sqrt 6" ""unit"/s#