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平面向量数量积的意义

> 设A（a，1），B（2，b），C（4，5）为坐标平面上三点，O为坐标原点，若与在方向上的投影相同，则a与b满足的关系式为 [ ] A．4a﹣5b=3 B．5a﹣4b=3 C．4a+5b=14 D．5a+4b=14

问题：

发布时间：2024-09-10

设A（a，1），B（2，b），C（4，5）为坐标平面上三点，O为坐标原点，若与在方向上的投影相同，则a与b满足的关系式为
[ ]
A．4a﹣5b=3
B．5a﹣4b=3
C．4a+5b=14
D．5a+4b=14

参考答案：

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设A（a，1），B（2，b），C（4，5）为坐标平面上三点，O为坐标原点，若 与 在 方向上的投影相同，则a与b满足的关系式为 [ ] A．4a﹣5b=3 B．5a﹣4b=3 C．4a+5b=14 D．5a+4b=14

可能感兴趣的题目：

设A（a，1），B（2，b），C（4，5）为坐标平面上三点，O为坐标原点，若与在方向上的投影相同，则a与b满足的关系式为
[ ]
A．4a﹣5b=3
B．5a﹣4b=3
C．4a+5b=14
D．5a+4b=14