Homework Statement
Suppose that I\subseteq J are subfields of \mathbb{C}(t_1,...,t_n) (that is, subsets closed under the operations +, - , \times, \div), and J is generated by J_1,...,J_r where I \subseteq J_j \subseteq J for each j and J_j:I is radical. By induction on r, prove that J:I is...