منابع مشابه
A Theorem about Three Quadratic Forms
σ1[x] · σ2[x]. Therefore, if we find s > 0 such that σ[x] < 0 for some x satisfying σ2[x]/σ1[x] = s 2, we get a contradiction with (1.1). Consider the set S ⊂ (0,∞) × (0,∞) consisting of all pairs (s, t) such that σs[x] < 0 for some x satisfying σ2[x]/σ1[x] = t 2. We want to show that (α,α) ∈ S for some α > 0, which gives us the contradiction. Since all forms are non-zero, there exist vectors x...
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ژورنال
عنوان ژورنال: Bulletin of the American Mathematical Society
سال: 1938
ISSN: 0002-9904
DOI: 10.1090/s0002-9904-1938-06778-x