linear problems的用法和樣例：
例句
- Both methods result in tridiagonal systems of linear equations that can be solved efficiently.
兩種方法都形成了有效求解的三對角線的線性方程組。 - The numerical results of some test problems show that the two-grid methods are robust in solving regularized systems.
試驗問題的數值結果表明，雙網格迭代方法求解正則化后的對稱正定線性方程組效果很好。
