一道数学题 怎么求解
一道数学题 怎么求解
日期：2021-06-07 12:41:23 人气：1
1)[C(100,98)+C(100,97)]/A(101,3)=C(101,98)/A(101,3)=C(101,3)/A(101,3)
=[A(101,3)/A(3,3)]/A(101,3)=1/A(3,3)=1/6
2)C(2,2)+C(3,2)+C(4,2)+...+C(10,2)=[C(3,3)+C(3,2)[+C(4,2)+...+C(10,2)
=C(4,3)+C(4,2)+...+C(10,2)=C(1
=[A(101,3)/A(3,3)]/A(101,3)=1/A(3,3)=1/6
2)C(2,2)+C(3,2)+C(4,2)+...+C(10,2)=[C(3,3)+C(3,2)[+C(4,2)+...+C(10,2)
=C(4,3)+C(4,2)+...+C(10,2)=C(1