If a = 3i - 2j + k and b = i + 2j + 5k, then the unit vector along a - b is

If a = 3i - 2j + k, b = -i + j + k then the unit vector parallel to the vector a + b is

If a = i + j - 2k, b = -i + 2j + k, c = i - 2j + 2k, then a unit vector parallel to a + b + c =

If A = i + 2j + 3k and B = 2i - j + 4k, then the position vectors of the points of trisection are

If a = i + j, b = j + k and c = i + k then a unit vector in the direction of a - 2b + 3c is

If the position vectors of A, B are 2i - 9j - 4k, 6i - 3j + 8k then the unit vector in the direction of vec(A)B is

If vec a = i+j-2k, vec b = -i+2j+k and vec c = i-2j+2k then a unit vector parallel to vec a + vec b + vec c is