أرسل هذا في رسالة قصيرة: Direct Fifth Order Block Backward Differentiation Formulas for Solving Second Order Ordinary Differential Equations

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| |  | ||   / _ \\   /  ___|| | || | ||  /_   _// 
| |/\| ||  / //\ \\ | // __   | || | ||    | ||   
|  /\  || |  ___  ||| \\_\ || | \\_/ ||   _| ||   
|_// \_|| |_||  |_|| \____//   \____//   /__//    
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