On the 2-class group of \(\mathbb{Q}(\sqrt{d},i)\)
The author determines all positive squarefree integers \(d\) such that the \(2\)-class group of the biquadratic number field \(\mathbb Q(\sqrt{d},i)\) has type \((2,2)\). The methods used include genus theory, the class number formula for biquadratic extensions, and the ambiguous class number formula.
scientific article; zbMATH DE number 1279152