Given fundamental discriminants d=4m with class number h(−d)=4, there are exactly five m=2p for prime p, namely p=7,17,23,41,71. The cases p=17,41 were in Entry 115 while p=7,23,71 which are p≡3mod4 will be tackled here. Define the two simple functionsα(n)=(n+√n2−1)2β(n)=(√n2−2+√n2−1)2and letn1=2+2√2n2=26+18√2n3=1450+1026√2Then the first quartic unit can be an eighth power
α(n1)=128(√0+√2+√4+√2)8α(n2)=128(√4+3√2+√8+3√2)8α(n3)=128(√36+27√2+√40+27√2)8 while the second is a product of quadratic units
β(n1)=U7√U14=(8+3√7)(2√2+√7)β(n2)=U23√U46=(25+5√23)(78√2+23√23)β(n3)=U71√U142=(3480+413√71)(1710√2+287√71) which gives the radical expressions of 1λ(√−14)=α(n1)β(n1),n1=2+2√21λ(√−46)=α(n2)β(n2),n2=26+18√21λ(√−142)=α(n3)β(n3),n3=1450+1026√2 And since β(n)=(√n2−2+√n2−1)2, then they are also nested radicals that use only √2.
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