The Research On The Class Number Of Quadratic Field

If I(k) presents all the fractional ideal in the number field k and P(k)respects the principal fractional ideal in the number field k, then the factor group h(k)=I(k)/P(k) are called, the ideal class number of the number field k,which is short for the class number of k. h(k) is the important Invariant in the number field k, which is one of the central subject research of the algebraic number theory for the class number of number field and the structure of the class number.To use the knowledge of the algebraic number theory, the author calculates the class number of the imaginary quadratic fieldQ(-d)and the real quadratic fieldQ(d),(d=150-200), and then gives the fundamental unit of the real secondary domain Q(d).