Hello everyone, I apologize for my english.
I have a little ploblem in a count:
Let Z a (Zariski) closed set in with . Consider the incidence variety and the second factor projection
.
Let smooth then proove that
is surjective if and only if , i.e. the projectif tangent space to Z at p, intersects trasversally .
Note: if (Zariski) closed, ( is the set of smooth point of Z) then Z intersects trasversally W if and only if the map
given by is surjective.
Thanks at everyone.