Can somebody check the following answers are correct and give any guidance on the others?
I was given F = (x^3, By^2, xyz)
(i) del.F = 3x^2 + 2By + xy
(ii) del.(del.F) = 6x + 2B // Differentiating (i)
(iii) del x F = (xz)i - (yz)j
(iv) del x (del x F)
Not sure how to do this?
Do you just differentiate F twice wrt x,y,z and then add them?