Let lk be a extension of fields st lk 2 show that if k

Question

Problem:

Let L:K be a extension of fields s.t . [L:K] = 2. Show that if K does not have characteristic 2, then there exists θEL such that L = K(θ) and θ²EK.

Additional Information:

This problem is basically from Mathematics as well as it is about calculation of extension of fields.

Note: The solution is in handwritten format.