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平面向量数量积的意义

> 平面向量 a ={6，-3}， b ={1，2}，（1）求 | a |、 | b |及 a • b 的值；（2）是否存在实数t，使 x = a +(t-6) b ， y = a +t b ，且 x ⊥ y ．若存在求出实数t的值；若不存在，请说明理由．

问题：

发布时间：2024-09-10

平面向量

a

={6，-3}，

b

={1，2}，
（1）求 |

a

|、 |

b

|及

a

•

b

的值；
（2）是否存在实数t，使

x

=

a

+(t-6)

b

，

y

=

a

+t

b

，且

x

⊥

y

．若存在求出实数t的值；若不存在，请说明理由．

参考答案：

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平面向量 a ={6，-3}， b ={1，2}， （1）求 | a |、 | b |及 a • b 的值； （2）是否存在实数t，使 x = a +(t-6) b ， y = a +t b ，且 x ⊥ y ．若存在求出实数t的值；若不存在，请说明理由．

可能感兴趣的题目：

平面向量

a

={6，-3}，

b

={1，2}，
（1）求 |

a

|、 |

b

|及

a

•

b

的值；
（2）是否存在实数t，使

x

=

a

+(t-6)

b

，

y

=

a

+t

b

，且

x

⊥

y

．若存在求出实数t的值；若不存在，请说明理由．