๐Ÿ—๏ธ ฮ˜ฯฯตฮทฮ ฮฑฯ„ฯ€๐Ÿšง (under construction)

Field Extension must Adjoin a Square Root
Suppose that E is a field extension of Q of degree 2. Prove that E=Q(a) for some aโˆˆQ such that aโˆ‰Q