论文标题
Chebyshev类型的交替定理，以最佳近似为两个代数
A Chebyshev type alternation theorem for best approximation by a sum of two algebras
论文作者
论文摘要
令$ x $为紧凑的公制空间，$ c（x）$是$ x $上连续实价函数的空间，而$ a_1 $，$ a_2 $为两个$ c（x）$包含常数功能的封闭sibergebras。我们考虑了$ a_1+a_2 $的元素在c（x）$中近似$ f \的近似问题。我们证明了a_1+a_2 $中函数$ u_0 \的chebyshev类型交替定理，以成为$ f $的最佳近似值。
Let $X$ be a compact metric space, $C(X)$ be the space of continuous real-valued functions on $X$, and $A_1$, $A_2$ be two closed subalgebras of $C(X)$ containing constant functions. We consider the problem of approximation of a function $f\in C(X)$ by elements from $A_1+A_2$. We prove a Chebyshev type alternation theorem for a function $u_0\in A_1+A_2$ to be a best approximation to $f$.
