The unit normal vector to the line joining `i-j` and `2i+ 3j` and pointing towards the origin is

The unit vector normal to the plane containing a = I - j - k and b = I + j + k is

A unit vector normal to the plane through the points i,2j and 3k is

The position vector of a point laying on the line joining the points whose position vectors are i+j-k and i-j+k is

The position vector of a point lying on the line joining the points whose position vectors are bar(i)+bar(j)-bar(k) and bar(i)-bar(j)+bar(k) is

The vector equation of the line passing through the point i-2j+k and perpendicular to the vectors 2i-3j-k,i+4j-2k is